Complete Fifth Ray Amputation with Peroneal Tendon ...
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The traditional partial fifth ray amputation technique for treatment of wounds isolated to the fifth toe and metatarsal phalangeal joint (MPJ) area involves removal of the fifth toe and metatarsal head. The goal with partial fifth ray amputation is to maintain at least 50% of the proximal fifth metatarsal with the intent to maintain foot structure and preserve the peroneus brevis attachment. More proximal wounds at the midshaft or base of the fifth metatarsal which may be associated with prior partial ray amputation, Charcot arthropathy or decubitus ulceration are not amenable to this preferred amputation approach. Surgeons are reluctant to remove the entire fifth ray yet optimum treatment frequently involves combined medical and surgical treatment with the intent to resolve the infection, correct bone deformity, and close the wound deficit all while preserving foot function. Partial fifth ray amputation is a safe and reliable procedure but lateral column reulceration can occur in patients with cavovarus foot structure, severe tailors bunion with wide fourth-fifth intermetatarsal angle, and metatarsus adductus foot deformity. Medical comorbidities such as diabetes mellitus (DM), peripheral vascular disease (PVD), neuropathy, history of MRSA/VRE infection, chronic kidney disease (CKD) and Charcot-Marie-Tooth (CMT) also complicate the condition and can contribute to the failure of fifth ray amputation requiring further surgery. Complete fifth ray amputation is sometimes indicated for complicated lateral foot wounds with care taken to resolve midfoot wounds and osteomyelitis while preserving the functional integrity of the foot. Our typical approach involves a two stage operation with initial resection of the fifth toe and entire fifth metatarsal followed by delayed cuboid remodeling and peroneal tendon transfer 2 weeks later. Insertion of antibiotic impregnated beads and flap coverage of the wound are commonly incorporated during the stage 1 procedure. This technique allows for complete coverage of the wound deficit, proper diagnosis of osteomyelitis by bone biopsy, confirmation of clean bone margin, correction of underlying bone deformity, and tendon rebalancing. Our preferred surgical technique has been previously described by Boffeli and Abben (1) but no outcomes have been published regarding short term healing rates or limb salvage rate. The purpose of this retrospective review was to evaluate the outcomes of consecutive patients who underwent complete fifth ray amputation from 2006 through 2015 and present the short term wound healing rates and intermediate outcomes of the procedure. Figure 5: Intermediate to long- term outcome (n=20) Figure 2: Stage 1 procedure with complete fifth ray amputation and antibiotic bead placement (a) A dorsal flap is preserved when amputating the 5 th toe. (b) The incision is extended proximally allowing fifth metatarsal resection with care taken to not violate the fourth metatarsal or cuboid during stage 1 surgery. (c) A string of antibiotic impregnated methyl methacrylate beads are then placed within the void created by removal of the fifth metatarsal. (d) Primary or flap closure over antibiotic beads. No drain is used as local hematoma aides in the elution of antibiotics to the surrounding tissue and bone. Note how the flap was advanced to cover the plantar MPJ wound. Troy J. Boffeli, DPM, FACFAS; Steven R. Smith, DPM; Kyle W. Abben, DPM, AACFAS Regions Hospital / HealthPartners Institute for Education and Research - Saint Paul, MN Complete Fifth Ray Amputation with Peroneal Tendon Transfer to the Cuboid: A Retrospective Review of Consecutive Cases Involving Lateral Column Diabetic Foot Ulceration and Osteomyelitis STATEMENT OF PURPOSE LITERATURE REVIEW MATERIALS AND METHODS RESULTS ANALYSIS & DISCUSSION REFERENCES Figure 1: Incision design based on ulcer location Fig. 1a-d. A variety of incision options are available for complete 5 th ray amputation depending on ulcer location. The incision is designed to excise the ulcer and incorporate amputation of the fifth toe. Removal of the entire fifth metatarsal creates laxity in the tissues, which allows incorporation of advancement and rotational flaps for coverage of fairly large wound defects. Wound locations include (a) metatarsal head and base, (b) lateral metatarsal base, (c) plantar midshaft stump, and (d) plantar Charcot wound. Figure 7: Nine year follow-up after complete fifth ray resection with peroneal tendon transfer to the cuboid HealthPartners/Regions Hospital Level I Adult & Level I Pediatric Trauma Center Figure 3: Stage 2 procedure with antibiotic bead removal and peroneus longus tendon transfer into the cuboid (a) The distal sutures are left in place with the stage 2 procedure. The proximal portion of the incision is opened to allow removal of the antibiotic beads and hematoma washout. (b) The prominent distal aspect of the cuboid is then smoothed to remove any plantar and lateral bony prominences with a portion of b one sent for clean margin biopsy (arrow). (c) The incision is then lengthened proximally if needed allowing exposure to the peroneus longus tendon for transfer into a drill hole in the cuboid using an absorbable soft tissue anchor. (d) The wound is closed primarily and sutures are commonly left in place for another 2-4 weeks. Figure 4: Preoperative 5 th ray ulcer location (n=20) 6 3 1 10 HEAD BASE HEAD AND BASE STUMP ULCERATION AFTER PARTIAL 5TH RAY AMPUTATION An IRB approved retrospective review was performed of consecutive patients that underwent complete fifth ray resection during a nine year span (2006-2015) by one surgeon. Data collected included patient demographics, comorbidities, history of partial fifth ray resection, ulcer location, use of antibiotic beads, incorporation of peroneal tendon transfer, bone culture results, pathology results, success with initial surgical wound healing, final outcome, and follow-up time (in months). PROCEDURE Table 1: Patient demographics Average Age 55.7 Sex (M:F) 15 male, 5 female Diabetes 16/20 Peripheral Neuropathy 20/20 Chronic Kidney Disease 7/20 Charcot Marie Tooth 2/20 Peripheral Vascular Disease 6/20 History of MRSA/VRE infection 8/20 ANALYSIS AND DISCUSSION Previous literature has discussed fifth metatarsal resection in conjunction with peroneal tendon transfer as a way to treat cavovarus foot deformity and osteomyelitis to the fifth metatarsal. This retrospective review of consecutive patients treated with fifth ray amputation with peroneal tendon transfer and antibiotic bead placement when necessary has shown to be a reproducible procedure with fair outcomes in a difficult patient population. CONCLUSION 1. Boffeli T and Abben K. "Complete Fifth Ray Amputation with Peroneal Tendon Transfer—A Staged Surgical Protocol." The Journal of Foot and Ankle Surgery 51.5 (2012): 696-701. 2. Altindas M, Ceber M, Kilic A, Sarac M, Diyarbakirli M, and Baghaki S. "A Reliable Method for Treatment of Nonhealing Ulcers in the Hindfoot and Midfoot Region in Diabetic Patients." Annals of Plastic Surgery 70.1 (2013): 82-87. 3. Roper R and Altman M. Fifth metatarsal excision with peroneus brevis transfer. A case report. Journal of the American Podiatric Medical Association: November 1985, Vol. 75, No. 11, pp. 607-610.4 4. Shariff R, Myerson M, and Palmanovich E. "Resection of the Fifth Metatarsal Base in the Severe Rigid Cavovarus Foot." Foot & Ankle International 35.6 (2014): 558-65. 5. Clark G, Lui E, and Cook K. "Tendon Balancing in Pedal Amputations." Clinics in Podiatric Medicine and Surgery 22.3 (2005): 447-67. 6. Schoenhaus J, Jay R, and Schoenhaus H. "Transfer of the Peroneus Brevis Tendon After Resection of the Fifth Metatarsal Base." Journal of the American Podiatric Medical Association 94.6 (2004): 594-60. 7. Carlson R, Smith N, Stuck R, Sage R. Dislocation of the fifth metatarsal base following partial fourth and fifth ray amputation. A Case Report. Journal of the American Podiatric Medical Association 102(1): 71-74, 2012. 8. Eletheriadou L, Tentolouris N, Argiana V, Jude E, and Boulton A. "Methicillin-Resistant Staphylococcus Aureus in Diabetic Foot Infection." Springer Link, 19 Sept. 2012. Web. 04 Nov. 2015.B Figure 6: Preop and 6 week postoperative radiographs a d c b b d c The 2 stage approach to complete fifth ray amputation including antibiotic bead placement, peroneus longus tendon transfer to the cuboid and flap closure was previously published by Boffeli and Abben in 2012 (1).The surgical technique is presented in Figures 1-3. a c d a 10 4 1 4 1 Healed without further intervention BKA Symes Amputation TMA Revision bone remodeling b Osteomyelitis of the fifth metatarsal is a difficult condition to treat and complete fifth ray amputation has been shown to be beneficial for both eradication of the infection and treatment of lateral column overload (2). We typically perform complete fifth ray amputation when greater than 50 percent of the metatarsal needs to be removed due to extent of infection or wound location. It is prudent to avoid leaving a prominent metatarsal base for fear of recurrent ulceration in this fragile population (1). The literature supports resection of infected or necrotic bone, as well as removal of bony prominences that prevent wound healing, although careful tendon balancing of the foot must be taken into consideration if altering tendon insertions (3-7). This is certainly the case when removing the base of the fifth metatarsal with subsequent loss of the peroneus brevis tendon insertion. The concern with removing the entire fifth metatarsal is that if the pronatory power of the peroneus brevis tendon is not maintained. The supinatory strength of the posterior tibial tendon may then force the foot into an adductovarus deformity (3). If the peroneal tendon is viable, tendon transfer should be attempted (4). Various locations for transfer of the peroneus brevis tendon have been described, including transfer into the cuboid, base of the fourth metatarsal, and side-to-side anastomosis with the peroneus longus tendon (6). Altman and Rick described transfer of the peroneus brevis tendon to the cuboid after removal of the fifth metatarsal base. They also reported a shortcoming of fifth ray amputation being dislocation of the fifth metatarsal base leading to prominence along the lateral column (3). This complication was also reported by Carlson in 2012 with similar surgical repair (7). Peroneus longus tendon transfer into the cuboid is our preferred technique as it secondarily creates dorsiflexion of the first metatarsal to address preexisting cavus deformity yet maintains strong eversion strength. The peroneus brevis tendon is also commonly diseased when wounds or infection are present at the fifth metatarsal base. The staged approach for complete amputation of the fifth metatarsal and peroneus longus tendon transfer with antibiotic bead placement was previously published by Abben and Boffeli in 2012 (1). The technique outlined our current 2 stage approach with the first stage involving removal of the infected ulcer, complete fifth ray amputation and closure over an antibiotic bead chain. The stage 1 incision is designed to create a flap for closure of the original wound deficit. The stage 2 procedure involves removal of the antibiotic bead chain and peroneus longus tendon transfer into the cuboid if the soft tissue and bone are amenable. The typical patient who requires this end stage intervention has failed more conservative treatment and is at high risk for higher level amputation due to associated comorbidities including poor circulation. Short or long term outcomes have not been reported for this approach. This retrospective review was performed to assess the outcomes associated with patients who underwent complete fifth ray amputation with incorporation of antibiotic bead placement and delayed peroneal tendon transfer when indicated. The medical records of 20 consecutive patients who had undergone complete fifth ray resection in a nine year period, from 2006 to 2015. Of the 20 patients, 15 were male and 5 were female, with a mean age of 55.68 (range 42 to 77) years. Average follow-up was 38.4 (range 2.9 to 105) months. Patient demographics are presented in Table 1. For patients requiring complete fifth ray amputation, 6/20 (30%) patients had preoperative ulcerations located at the fifth metatarsal head, 3/20 (15%) had ulcers at the base of the fifth metatarsal, 1/20 (5%) patient had ulcerations located at the metatarsal base and head, and 10/20 (50%) patients had previous partial fifth ray resection with midshaft stump ulceration. This data is presented in Figure 4. Regarding adjunctive procedures, 15/20 (75%) had a 2 staged approach. The decision for staged surgery was based on severity of infection and desire for implantable beads or tendon transfer. 10/20 (50%) patients had antibiotic beads placed during stage 1 surgery while 16/20 (80%) patients had peroneus longus tendon transfer to the cuboid. Of those requiring a stage 2 procedure, antibiotic beads were implanted in 10/15 (66%) cases, and peroneal tendon transfer was performed in 13/15 (86.6%) cases. 15/20 (75%) patients had positive bone cultures during the stage 1 procedure and 2/12 (16.6%) patients who had stage 2 biopsy had positive bone cultures at the proximal margin (cuboid). Pathology was positive for osteomyelitis in 12/20 (60%) patients during stage 1 and 1/12 (8.3%) patients who had stage 2 biopsy. The 3/20 (15%) patients with ongoing concern for cuboid osteomyelitis (positive culture or pathology) were treated with 6 weeks of IV antibiotics while the remaining 17/20 (85%) patients received a 2 week course of oral antibiotics following hospital discharge after stage 1 surgery. 1 patient had gouty tophi on pathologic biopsy and 1 patient had mycotic structures consistent with Madura foot. Success with initial healing was recorded in terms of complete incision healing at 6 and 10 week post- operative visits. 13/20 (65%) patients were completely healed at 6 weeks and an additional 1 patient was healed at 10 weeks. Those who were not healed at 10 weeks (6/20) were found to have more comorbidities than those who were not healed at 10 weeks. The patients not healed at 10 weeks had an average of 3.67 comorbidities versus 2.64 comorbidities in the group that was healed at 10 weeks of the 6 comorbidities that were assessed (DM, PVD, neuropathy, CKD, history of MRSA/VRE infection and CMT). Final outcome was determined by the need for further surgery on the operative extremity. Additional surgeries included four below-the-knee (BKA) amputations at an average of 25.9 months (range 6.0 - 55.2 months), one Symes amputation at 8 months, four transmetatarsal amputations at an average of 17.2 months (range 10.8 – 25), and two revision bone resection procedures at 3 and 19 months after complete fifth ray amputation (Figure 5). The remaining 9/20 patients required no further surgical treatment at final follow up. Of note, 5/6 (83.3%) patients not healed at 10 weeks required more surgery versus 5/14 (35.7%) of those healed at 10 weeks required further surgery. Those patients who required either BKA or Symes amputation were found to have on average 3.8 out of the 6 comorbidities analyzed. This study demonstrates that those at risk for higher level amputation are those with more comorbidities and those with delayed healing of the fifth ray amputation site. The patients that did not heal by 10 weeks were associated with more comorbidities including diabetes, peripheral neuropathy, history of drug-resistant bacterial infection, and peripheral arterial disease and were more likely to require further surgery. Included in those comorbidities, we assessed history of MRSA/VRE infection including 8/20 (40%) patients in this study. This has been shown to be a predictor of higher level amputations and present in 15-30% of diabetic foot infections (8). In our sample of patients, 3/20 patients with history of MRSA/VRE infection required higher level amputation including 2 patients with delayed wound healing who ultimately required BKA and 1 patient with wound dehiscence and eventual Symes amputation accounting for 3/5 (60%) of the patients without a functional foot at final follow-up. Patients at risk for delayed would healing are also those at risk for higher level amputation. 13/20 (65%) patients had incisions that were healed at 6 weeks and 14/20 (70%) were healed at 10 weeks. Healing was determined by the removal of sutures, no further wound care being performed and return to ambulation in shoes. A higher proportion of patients with delayed wound healing required higher level amputation than those with healed incisions, as 5/6 (83.3%) with delayed wound healing had further surgery versus 5/14 (35.7%) with healed incisions at 10 weeks required further surgery. An additional risk factor for delayed wound healing is continued osteomyelitis in the cuboid. 3/20 (15%) patients had either positive culture or pathology on proximal margin cuboid biopsy, 2 of whom required additional surgery including one with BKA 9.4 months later and one with revision bone resection after flap wound closure. 15/20 (75%) of the patients in this retrospective review were able to maintain functional ambulation without limb loss at average follow up of 38.4 months (2.9-105). A successful result is illustrated in Figure 7 by a patient who was followed 9 years post-operatively and continues to remain ulcer free and ambulates without the aid of a brace. Osteomyelitis of the fifth metatarsal can be a limb and life threatening infection and this was evident in 5/20 (25%) patients in this study who required late stage BKA or Symes amputation. BKA occurred an average of 25.9 months (range = 6 – 55.2 months) and Symes at 8 months after fifth ray amputation and was generally needed to treat recurrent wounds and infection. A functional limb was present at final follow-up in 15/20 (75%) of patients who had a bad enough lateral column wound condition to warrant complete fifth ray amputation, which would suggest reasonable success of the procedure considering the high risk nature of recurrent wounds and osteomyelitis in this fragile population. Limitations to this study are related to the retrospective and descriptive nature of the study design. The study followed a small cohort of patients and therefore was not able to draw statistically significant conclusions. This study was retrospective and although consecutive, some selection bias may be involved regarding procedure selection. Ulceration to the lateral column of the foot associated with peripheral neuropathy and cavus foot structure can lead to osteomyelitis to the fifth metatarsal that can prove difficult to treat. Components of the problem that need to be addressed include resection of the infected bone and soft tissue, bone biopsy to confirm diagnosis and direct antibiotic therapy and correction of the biomechanical issues that contributed to the recurrent or non-healing wound. Research has previously shown that transfer of the peroneal tendons can be used to rebalance the foot after partial or complete fifth ray resection (1,3,5,6). The results of the present study demonstrate that complete fifth ray amputation with adjunctive procedures as indicated achieves the stated goals of the procedure but does not prevent further ulceration or amputation for all patients due to complex comorbid conditions including underlying deformity, DM and neuropathic ulceration.
Transcript of Complete Fifth Ray Amputation with Peroneal Tendon ...
The traditional partial fifth ray amputation technique for treatment of wounds isolated to the fifth toe and metatarsal phalangeal joint (MPJ) area involves removal of the fifth toe and metatarsal head. The goal with partial fifth ray amputation is to maintain at least 50% of the proximal fifth metatarsal with the intent to maintain foot structure and preserve the peroneus brevis attachment. More proximal wounds at the midshaft or base of the fifth metatarsal which may be associated with prior partial ray amputation, Charcot arthropathy or decubitus ulceration are not amenable to this preferred amputation approach. Surgeons are reluctant to remove the entire fifth ray yet optimum treatment frequently involves combined medical and surgical treatment with the intent to resolve the infection, correct bone deformity, and close the wound deficit all while preserving foot function. Partial fifth ray amputation is a safe and reliable procedure but lateral column reulceration can occur in patients with cavovarus foot structure, severe tailors bunion with wide fourth-fifth intermetatarsal angle, and metatarsus adductus foot deformity. Medical comorbidities such as diabetes mellitus (DM), peripheral vascular disease (PVD), neuropathy, history of MRSA/VRE infection, chronic kidney disease (CKD) and Charcot-Marie-Tooth (CMT) also complicate the condition and can contribute to the failure of fifth ray amputation requiring further surgery.
Complete fifth ray amputation is sometimes indicated for complicated lateral foot wounds with care taken to resolve midfoot wounds and osteomyelitis while preserving the functional integrity of the foot. Our typical approach involves a two stage operation with initial resection of the fifth toe and entire fifth metatarsal followed by delayed cuboid remodeling and peroneal tendon transfer 2 weeks later. Insertion of antibiotic impregnated beads and flap coverage of the wound are commonly incorporated during the stage 1 procedure. This technique allows for complete coverage of the wound deficit, proper diagnosis of osteomyelitis by bone biopsy, confirmation of clean bone margin, correction of underlying bone deformity, and tendon rebalancing. Our preferred surgical technique has been previously described by Boffeli and Abben (1) but no outcomes have been published regarding short term healing rates or limb salvage rate. The purpose of this retrospective review was to evaluate the outcomes of consecutive patients who underwent complete fifth ray amputation from 2006 through 2015 and present the short term wound healing rates and intermediate outcomes of the procedure.
Figure 5: Intermediate to long-term outcome (n=20)
Figure 2: Stage 1 procedure with complete fifth ray amputation and antibiotic bead placement
(a) A dorsal flap is preserved when amputating the 5th toe. (b) The incision is extended proximally allowing fifth metatarsal resection with care taken to not violate the fourth metatarsal or cuboid during stage 1 surgery. (c) A string of antibiotic impregnated methyl methacrylate beads are then placed within the void created by removal of the fifth metatarsal. (d) Primary or flap closure over antibiotic beads. No drain is used as local hematoma aides in the elution of antibiotics to the surrounding tissue and bone. Note how the flap was advanced to cover the plantar MPJ wound.
Troy J. Boffeli, DPM, FACFAS; Steven R. Smith, DPM; Kyle W. Abben, DPM, AACFAS Regions Hospital / HealthPartners Institute for Education and Research - Saint Paul, MN
Complete Fifth Ray Amputation with Peroneal Tendon Transfer to the Cuboid: A Retrospective Review of
Consecutive Cases Involving Lateral Column Diabetic Foot Ulceration and Osteomyelitis
STATEMENT OF PURPOSE
LITERATURE REVIEW
MATERIALS AND METHODS
RESULTS
ANALYSIS & DISCUSSION
REFERENCES
Figure 1: Incision design based on ulcer location
Fig. 1a-d. A variety of incision options are available for complete 5th ray amputation depending on ulcer location. The incision is designed to excise the ulcer and incorporate amputation of the fifth toe. Removal of the entire fifth metatarsal creates laxity in the tissues, which allows incorporation of advancement and rotational flaps for coverage of fairly large wound defects. Wound locations include (a) metatarsal head and base, (b) lateral metatarsal base, (c) plantar midshaft stump, and (d) plantar Charcot wound.
Figure 7: Nine year follow-up after complete fifth ray resection with peroneal tendon transfer to the cuboid
HealthPartners/Regions Hospital Level I Adult & Level I Pediatric Trauma Center
Figure 3: Stage 2 procedure with antibiotic bead removal and peroneus longus tendon transfer into the cuboid
(a) The distal sutures are left in place with the stage 2 procedure. The proximal portion of the incision is opened to allow removal of the antibiotic beads and hematoma washout. (b) The prominent distal aspect of the cuboid is then smoothed to remove any plantar and lateral bony prominences with a portion of bone sent for clean margin biopsy (arrow). (c) The incision is then lengthened proximally if needed allowing exposure to the peroneus longus tendon for transfer into a drill hole in the cuboid using an absorbable soft tissue anchor. (d) The wound is closed primarily and sutures are commonly left in place for another 2-4 weeks.
Figure 4: Preoperative 5th ray ulcer location (n=20)
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3 1
10
HEAD
BASE
HEAD AND BASE
STUMP ULCERATIONAFTER PARTIAL 5THRAY AMPUTATION
An IRB approved retrospective review was performed of consecutive patients that underwent complete fifth ray resection during a nine year span (2006-2015) by one surgeon. Data collected included patient demographics, comorbidities, history of partial fifth ray resection, ulcer location, use of antibiotic beads, incorporation of peroneal tendon transfer, bone culture results, pathology results, success with initial surgical wound healing, final outcome, and follow-up time (in months).
PROCEDURE
Table 1: Patient demographics Average Age 55.7
Sex (M:F) 15 male, 5 female
Diabetes 16/20
Peripheral Neuropathy 20/20
Chronic Kidney Disease 7/20
Charcot Marie Tooth 2/20
Peripheral Vascular Disease 6/20
History of MRSA/VRE infection 8/20
ANALYSIS AND DISCUSSION
Previous literature has discussed fifth metatarsal resection in conjunction with peroneal tendon transfer as a way to treat cavovarus foot deformity and osteomyelitis to the fifth metatarsal. This retrospective review of consecutive patients treated with fifth ray amputation with peroneal tendon transfer and antibiotic bead placement when necessary has shown to be a reproducible procedure with fair outcomes in a difficult patient population.
CONCLUSION
1. Boffeli T and Abben K. "Complete Fifth Ray Amputation with Peroneal Tendon Transfer—A Staged Surgical Protocol." The Journal of Foot and Ankle Surgery 51.5 (2012): 696-701.
2. Altindas M, Ceber M, Kilic A, Sarac M, Diyarbakirli M, and Baghaki S. "A Reliable Method for Treatment of Nonhealing Ulcers in the Hindfoot and Midfoot Region in Diabetic Patients." Annals of Plastic Surgery 70.1 (2013): 82-87.
3. Roper R and Altman M. Fifth metatarsal excision with peroneus brevis transfer. A case report. Journal of the American Podiatric Medical Association: November 1985, Vol. 75, No. 11, pp. 607-610.4
4. Shariff R, Myerson M, and Palmanovich E. "Resection of the Fifth Metatarsal Base in the Severe Rigid Cavovarus Foot." Foot & Ankle International 35.6 (2014): 558-65.
5. Clark G, Lui E, and Cook K. "Tendon Balancing in Pedal Amputations." Clinics in Podiatric Medicine and Surgery 22.3 (2005): 447-67.
6. Schoenhaus J, Jay R, and Schoenhaus H. "Transfer of the Peroneus Brevis Tendon After Resection of the Fifth Metatarsal Base." Journal of the American Podiatric Medical Association 94.6 (2004): 594-60.
7. Carlson R, Smith N, Stuck R, Sage R. Dislocation of the fifth metatarsal base following partial fourth and fifth ray amputation. A Case Report. Journal of the American Podiatric Medical Association 102(1): 71-74, 2012.
8. Eletheriadou L, Tentolouris N, Argiana V, Jude E, and Boulton A. "Methicillin-Resistant Staphylococcus Aureus in Diabetic Foot Infection." Springer Link, 19 Sept. 2012. Web. 04 Nov. 2015.B
Figure 6: Preop and 6 week postoperative radiographs
a
d c
b
b
d c
The 2 stage approach to complete fifth ray amputation including antibiotic bead placement, peroneus longus tendon transfer to the cuboid and flap closure was previously published by Boffeli and Abben in 2012 (1).The surgical technique is presented in Figures 1-3.
a c d
a
10
4
1
4
1 Healed withoutfurther intervention
BKA
Symes Amputation
TMA
Revision boneremodeling
b
Osteomyelitis of the fifth metatarsal is a difficult condition to treat and complete fifth ray amputation has been shown to be beneficial for both eradication of the infection and treatment of lateral column overload (2). We typically perform complete fifth ray amputation when greater than 50 percent of the metatarsal needs to be removed due to extent of infection or wound location. It is prudent to avoid leaving a prominent metatarsal base for fear of recurrent ulceration in this fragile population (1). The literature supports resection of infected or necrotic bone, as well as removal of bony prominences that prevent wound healing, although careful tendon balancing of the foot must be taken into consideration if altering tendon insertions (3-7). This is certainly the case when removing the base of the fifth metatarsal with subsequent loss of the peroneus brevis tendon insertion. The concern with removing the entire fifth metatarsal is that if the pronatory power of the peroneus brevis tendon is not maintained. The supinatory strength of the posterior tibial tendon may then force the foot into an adductovarus deformity (3). If the peroneal tendon is viable, tendon transfer should be attempted (4). Various locations for transfer of the peroneus brevis tendon have been described, including transfer into the cuboid, base of the fourth metatarsal, and side-to-side anastomosis with the peroneus longus tendon (6). Altman and Rick described transfer of the peroneus brevis tendon to the cuboid after removal of the fifth metatarsal base. They also reported a shortcoming of fifth ray amputation being dislocation of the fifth metatarsal base leading to prominence along the lateral column (3). This complication was also reported by Carlson in 2012 with similar surgical repair (7). Peroneus longus tendon transfer into the cuboid is our preferred technique as it secondarily creates dorsiflexion of the first metatarsal to address preexisting cavus deformity yet maintains strong eversion strength. The peroneus brevis tendon is also commonly diseased when wounds or infection are present at the fifth metatarsal base. The staged approach for complete amputation of the fifth metatarsal and peroneus longus tendon transfer with antibiotic bead placement was previously published by Abben and Boffeli in 2012 (1). The technique outlined our current 2 stage approach with the first stage involving removal of the infected ulcer, complete fifth ray amputation and closure over an antibiotic bead chain. The stage 1 incision is designed to create a flap for closure of the original wound deficit. The stage 2 procedure involves removal of the antibiotic bead chain and peroneus longus tendon transfer into the cuboid if the soft tissue and bone are amenable. The typical patient who requires this end stage intervention has failed more conservative treatment and is at high risk for higher level amputation due to associated comorbidities including poor circulation. Short or long term outcomes have not been reported for this approach. This retrospective review was performed to assess the outcomes associated with patients who underwent complete fifth ray amputation with incorporation of antibiotic bead placement and delayed peroneal tendon transfer when indicated.
The medical records of 20 consecutive patients who had undergone complete fifth ray resection in a nine year period, from 2006 to 2015. Of the 20 patients, 15 were male and 5 were female, with a mean age of 55.68 (range 42 to 77) years. Average follow-up was 38.4 (range 2.9 to 105) months. Patient demographics are presented in Table 1. For patients requiring complete fifth ray amputation, 6/20 (30%) patients had preoperative ulcerations located at the fifth metatarsal head, 3/20 (15%) had ulcers at the base of the fifth metatarsal, 1/20 (5%) patient had ulcerations located at the metatarsal base and head, and 10/20 (50%) patients had previous partial fifth ray resection with midshaft stump ulceration. This data is presented in Figure 4. Regarding adjunctive procedures, 15/20 (75%) had a 2 staged approach. The decision for staged surgery was based on severity of infection and desire for implantable beads or tendon transfer. 10/20 (50%) patients had antibiotic beads placed during stage 1 surgery while 16/20 (80%) patients had peroneus longus tendon transfer to the cuboid. Of those requiring a stage 2 procedure, antibiotic beads were implanted in 10/15 (66%) cases, and peroneal tendon transfer was performed in 13/15 (86.6%) cases. 15/20 (75%) patients had positive bone cultures during the stage 1 procedure and 2/12 (16.6%) patients who had stage 2 biopsy had positive bone cultures at the proximal margin (cuboid). Pathology was positive for osteomyelitis in 12/20 (60%) patients during stage 1 and 1/12 (8.3%) patients who had stage 2 biopsy. The 3/20 (15%) patients with ongoing concern for cuboid osteomyelitis (positive culture or pathology) were treated with 6 weeks of IV antibiotics while the remaining 17/20 (85%) patients received a 2 week course of oral antibiotics following hospital discharge after stage 1 surgery. 1 patient had gouty tophi on pathologic biopsy and 1 patient had mycotic structures consistent with Madura foot. Success with initial healing was recorded in terms of complete incision healing at 6 and 10 week post-operative visits. 13/20 (65%) patients were completely healed at 6 weeks and an additional 1 patient was healed at 10 weeks. Those who were not healed at 10 weeks (6/20) were found to have more comorbidities than those who were not healed at 10 weeks. The patients not healed at 10 weeks had an average of 3.67 comorbidities versus 2.64 comorbidities in the group that was healed at 10 weeks of the 6 comorbidities that were assessed (DM, PVD, neuropathy, CKD, history of MRSA/VRE infection and CMT). Final outcome was determined by the need for further surgery on the operative extremity. Additional surgeries included four below-the-knee (BKA) amputations at an average of 25.9 months (range 6.0 - 55.2 months), one Symes amputation at 8 months, four transmetatarsal amputations at an average of 17.2 months (range 10.8 – 25), and two revision bone resection procedures at 3 and 19 months after complete fifth ray amputation (Figure 5). The remaining 9/20 patients required no further surgical treatment at final follow up. Of note, 5/6 (83.3%) patients not healed at 10 weeks required more surgery versus 5/14 (35.7%) of those healed at 10 weeks required further surgery. Those patients who required either BKA or Symes amputation were found to have on average 3.8 out of the 6 comorbidities analyzed.
This study demonstrates that those at risk for higher level amputation are those with more comorbidities and those with delayed healing of the fifth ray amputation site. The patients that did not heal by 10 weeks were associated with more comorbidities including diabetes, peripheral neuropathy, history of drug-resistant bacterial infection, and peripheral arterial disease and were more likely to require further surgery. Included in those comorbidities, we assessed history of MRSA/VRE infection including 8/20 (40%) patients in this study. This has been shown to be a predictor of higher level amputations and present in 15-30% of diabetic foot infections (8). In our sample of patients, 3/20 patients with history of MRSA/VRE infection required higher level amputation including 2 patients with delayed wound healing who ultimately required BKA and 1 patient with wound dehiscence and eventual Symes amputation accounting for 3/5 (60%) of the patients without a functional foot at final follow-up. Patients at risk for delayed would healing are also those at risk for higher level amputation. 13/20 (65%) patients had incisions that were healed at 6 weeks and 14/20 (70%) were healed at 10 weeks. Healing was determined by the removal of sutures, no further wound care being performed and return to ambulation in shoes. A higher proportion of patients with delayed wound healing required higher level amputation than those with healed incisions, as 5/6 (83.3%) with delayed wound healing had further surgery versus 5/14 (35.7%) with healed incisions at 10 weeks required further surgery. An additional risk factor for delayed wound healing is continued osteomyelitis in the cuboid. 3/20 (15%) patients had either positive culture or pathology on proximal margin cuboid biopsy, 2 of whom required additional surgery including one with BKA 9.4 months later and one with revision bone resection after flap wound closure. 15/20 (75%) of the patients in this retrospective review were able to maintain functional ambulation without limb loss at average follow up of 38.4 months (2.9-105). A successful result is illustrated in Figure 7 by a patient who was followed 9 years post-operatively and continues to remain ulcer free and ambulates without the aid of a brace. Osteomyelitis of the fifth metatarsal can be a limb and life threatening infection and this was evident in 5/20 (25%) patients in this study who required late stage BKA or Symes amputation. BKA occurred an average of 25.9 months (range = 6 – 55.2 months) and Symes at 8 months after fifth ray amputation and was generally needed to treat recurrent wounds and infection. A functional limb was present at final follow-up in 15/20 (75%) of patients who had a bad enough lateral column wound condition to warrant complete fifth ray amputation, which would suggest reasonable success of the procedure considering the high risk nature of recurrent wounds and osteomyelitis in this fragile population. Limitations to this study are related to the retrospective and descriptive nature of the study design. The study followed a small cohort of patients and therefore was not able to draw statistically significant conclusions. This study was retrospective and although consecutive, some selection bias may be involved regarding procedure selection.
Ulceration to the lateral column of the foot associated with peripheral neuropathy and cavus foot structure can lead to osteomyelitis to the fifth metatarsal that can prove difficult to treat. Components of the problem that need to be addressed include resection of the infected bone and soft tissue, bone biopsy to confirm diagnosis and direct antibiotic therapy and correction of the biomechanical issues that contributed to the recurrent or non-healing wound. Research has previously shown that transfer of the peroneal tendons can be used to rebalance the foot after partial or complete fifth ray resection (1,3,5,6). The results of the present study demonstrate that complete fifth ray amputation with adjunctive procedures as indicated achieves the stated goals of the procedure but does not prevent further ulceration or amputation for all patients due to complex comorbid conditions including underlying deformity, DM and neuropathic ulceration.
