Abstract

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Fibular head is often resected for reconstruction of defects of the distal radius. However little is known on the safety of such a procedure. We aim to evaluate the long-term donor-site morbidity following proximal fibular resection.
Patients and methods: Fourteen patients who underwent simple or marginal resection of the proximal fibula between 1990 and 2007 were reviewed. Subjective donor-site morbidity, knee and ankle range of motion and instability, sensory/ motor loss, gait, fibular regeneration were assessed.
Results: Mean age at surgery was 25 years; 6 were male, 8 were female; mean follow-up was 11 years. Abnormal clinical findings were present in 10 patients (71.4%): nine patients (64.3%) had Grade 2 varus laxity at the knee confirmed by stress radiographs; one had sensory loss in the distribution of the superficial peroneal nerve. Patients with varus laxity had significantly higher mean age at surgery than those without varus laxity (p=0.001). None had deformity of knee or ankle; range of movements was normal; all had normal tibio-talar angle; none had proximal migration of fibula. One patient demonstrated near-complete regeneration of the fibula.
Conclusion: Donor-site morbidity following simple and marginal resection of the proximal fibula is acceptable. Older patients had significantly higher risk of demonstrable clinical varus laxity. Proximal fibula resection in children appears to be safe, though a larger study is warranted before the results are extrapolated to larger populations.
Keywords: fibular head resection, varus laxity knee, fibula regeneration

Introduction

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Fibula is a common donor site in patients undergoing bone reconstruction. Its length, configuration, stability, and predictable vascular pedicle make it an ideal cortical bone graft donor [1,2]. Proximal fibula is often resected for reconstruction of the distal radius following excision of tumors [3,4,5].
Though there are a few studies assessing the morbidity following proximal fibula resection for malignant bone tumors, little is known of the safety of proximal fibula resection for reconstruction of bone defects[6,7,8,9]. The present study aims to assess the safety of proximal fibula resection by analysing patients undergoing simple or marginal resection of the proximal fibula.

Patients and Methods

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Hospital records of patients who underwent proximal fibular resection for various indications between 1990 and 2007 were accessed. Patients undergoing simple resection of the proximal fibula for bone transplantation or marginal resection for benign tumors of the proximal fibula were included in the study. Patients undergoing wide resection of the proximal fibula for malignant tumors or aggressive benign tumors were excluded. Nineteen patients satisfied the inclusion and exclusion criteria and were called for review. Fourteen patients were available for follow-up and were included in the study.
Subjective donor-site morbidity was determined with a questionnaire which recorded presence of pain, swelling, stiffness, weakness, instability, numbness, limp, restriction in daily activities, cosmetic disturbances, etc. Clinical examination assessed knee and ankle range of motion, varus, valgus, anteroposterior and rotatory instability at the knee, ankle instability, sensory/ motor loss, and gait among others.
Radiological assessment: All the patients had routine anteroposterior radiographs of their leg to assess the length of the resected fibula and of the distal remnant and also a standing anteroposterior radiograph of both ankles. Those patients who had clinical signs of varus instability of the knee underwent varus stress radiograph of the knee. Stress radiograph of both knees was taken with varus stress applied at 15-20o of knee flexion with the patient supine. Lateral knee joint space was measured in the varus stress films. A value of more than 5 mm compared to the normal side was considered as significant [10].
The anteroposterior radiograph of the ankles was used to study proximal migration of distal remnant of fibula and to assess valgus deformity. Proximal migration was measured as the distance between the tip of the lateral malleolus and the distal tibial articular surface in comparison with the opposite side [11]. Tibiotalar angle was calculated to assess ankle valgus [11,12]. A valgus change of 5o or more was regarded as ankle valgus deformity [12].
All patients had normal contralateral limb. Gait was assessed clinically in all patients. The ability of the patients to walk on heels, walk on outside foot and springing/hopping on donor leg was also assessed. Patients with findings of instability were asked to walk on a ramp with a side slope of 20 degrees to assess the effect of instability on gait.

Results

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Mean age of the patients at surgery was 25 years (range 8 to 59 years). There were 6 male and 8 female patients. Right side was operated in 7 and left side in 7 patients. Follow-up ranged from 3 years to 20 years (mean 11 years 1 month).
Seven patients underwent ‘simple’ resection for reconstruction of bone defect following upper limb surgery while seven others underwent ‘marginal’ resection for some benign tumor of the proximal fibula (Table 1). Simple resection consisted of subperiosteal resection of the proximal part of the fibula after detachment of the fibular collateral ligament and the biceps femoris from their insertions. Marginal excision entailed en bloc resection of the benign tumor through the pseudocapsule[7]. The stump of the collateral ligament and the tendon of the biceps femoris were reattached to the adjacent soft tissues after both procedures.Length of fibula resected ranged from 8 cm to 19.5 cm (mean 11. 5 cm). The mean percentage of fibula resected was 31.4% (23 to 49%). The length of the distal remnant ranged from 20 cm to 29 cm (mean 24.9 cm).
Subjective donor site symptoms: At final follow-up, two patients reported mild occasional pain at the donor site. One patient complained of numbness in the distribution of the superficial peroneal nerve. However none of them felt disabled by the symptoms. They did not have to seek any treatment for their complaints. There were no cosmetic problems from the scars. None of the patients complained of limp or difficulty in walking or running or instability of the knee or ankle.
Clinical Findings: There were abnormal clinical findings on examination in 10 of the 14 patients (71.4%): nine patients (64.3%) had Grade 2 varus laxity at the knee and one patient had sensory loss in the distribution of the superficial peroneal nerve. The age at surgery for the patients with varus laxity ranged from 20 to 59 years (mean – 32.33+12.06) while that of those without varus laxity ranged from 8 to 20 years (mean – 12.60+4.88). The mean age at surgery was significantly higher in those with varus laxity (p=0.001).
There was no significant difference in the duration of follow-up between patients with varus laxity (125.89+56.03 months) and those without varus laxity (148.40+74.95 months) (p=0.534) suggesting that the difference in follow-up duration did not influence the incidence of varus laxity.
However there was no deformity of the knee or ankle on inspection in the standing position and the range of movements of the knee and ankle were normal. None of the patients had ankle instability on clinical examination.
Gait: On functional evaluation, all the patients were able to walk on heels and on outside foot without any discomfort. All the patients were able to walk comfortably on a side slope of 20 degrees without any signs of instability.
Radiological assessment: Varus stress radiographs in patients with clinical varus knee laxity demonstrated increase in lateral knee joint space of >5 mm compared to the opposite side (Grade 2 instability) (Figure 1). However none of them had a difference of more than 10 mm (Grade 3 instability).
None of the patients had significant difference in the tibio-talar angle compared to the contralateral normal limb. None had proximal migration of the fibula.
Interestingly one patient, who underwent proximal fibula transplantation to the distal radius at 20 years of age, had near-complete regeneration of the fibula (Figure 2). None of the other seven patients who underwent subperiosteal resection for bone transplantation demonstrated any evidence of regeneration.

Discussions

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The fibula is an integral part of the structure of the ankle and knee joints and serves as an attachment for ligaments of the knee and ankle, the interosseous membrane of the leg and muscles of the lower extremity. Various biomechanical and cadaver studies have demonstrated the role of fibula in weight-transmission and normal function of the knee and ankle [13,14,15,16,17]. Alterations from normal in the motion of knee, ankle and foot have also been demonstrated in such biomechanical studies [17,18].
Uchiyama et al in their cadaver study found that whole fibula including the head of the fibula was essential for the stability of the ankle joint complex [19]. However few studies are available assessing the clinical outcomes of resection of the head of fibula.
Babhulkar et al retrospectively studied 104 patients who had resection of the fibula for various reasons. Twenty six of these patients had resection of the proximal fibula for reconstruction of excised distal radius. However none of the patients had any demonstrable instability of the knee [20].
Pho reported no instability after resection of the fibular head in three patients [21]. Murray and Schlafly reported lateral ligament laxity in nine of 18 patients who underwent proximal fibular resection, despite attaching the tendons and ligaments detached from the fibular head to the proximal fibula with drill holes [4].
Anderson and Green studied functional deficit following fibulectomy for bone graft in 10 patients of whom 2 underwent resection of the proximal fibula. They had reattached the biceps femoris tendon and the fibular collateral ligament to the proximal tibia. One of the two patients had 1+ laxity on clinical examination and 5 mm opening on Genucom examination compared to the opposite knee [18].
Draganich et al reported the effects of resection of proximal fibula on the stability of the knee and on gait in their series of 6 patients. The fibular collateral ligament and tendon of biceps femoris had been reattached to ligamentous and capsular structures. Based on instrumented analysis, they reported significantly increased anterior translation and varus and valgus rotation compared to the contralateral limb. The suggested that biceps femoris imparted a posteriorly directed force to the tibia and the iliotibial band and that detaching the biceps femoris, a dynamic restraint to anterior displacement of the tibia, resulted in the demonstrable anterior tibial translation [19].
Bickels et al analysed the outcomes of 24 patients who underwent proximal fibula resection for benign aggressive and malignant tumors. The lateral collateral ligament was reattached to the lateral tibial metaphysis using a staple with the knee in 20o flexion. Three patients (13%) had grade 1 instability and one (4%) had grade 2 instability. The authors recommend stapling of the lateral collateral ligament to the proximal tibial metaphysis as a safe and reliable technique to reconstruct knee stability after resection of the proximal fibula [20].
Recently Dieckmann et al reported the outcomes of proximal fibula resection in 47 malignant and 10 benign tumors of the proximal fibula. Of 45 patients who required resection of the lateral ligament complex, 41 underwent reconstruction with an anchor or transosseous suture of the remaining biceps femoris tendon and ligament. Thirteen of the 45 patients (28.9%) developed knee instability and required treatment with revision of the lateral ligament complex or orthoses [21].
In the present series, a large proportion (64.3%) of the patients had clinically and radiologically demonstrable knee joint laxity, though none of the patients had severe or symptomatic instability to warrant any treatment. The higher incidence of demonstrable knee instability is likely to be due to attachment of the collateral ligament and the tendon of the biceps femoris to the adjacent soft tissues rather than the proximal tibia.
Mean age was significantly higher in patients with varus laxity than in those without laxity. This is likely to be due to greater regeneration and healing potential in younger patients. This finding has not been reported earlier.
Though the patients were asymptomatic, collateral ligament injury is acknowledged to be a risk factor for knee osteoarthritis [22,23,24]. Reattaching the fibular collateral ligament and the tendon of the biceps femoris to the proximal tibial metaphysis is likely to prevent or reduce the severity of knee laxity [20,21], though a comparative study would be required to assert the same.
However, neither the present study nor other similar studies have demonstrated anterior translation of the tibia following resection of the fibular head. Nevertheless, the difference is likely to be due to the objective instrumented assessment by Draganich et al while most other reports have relied on clinical assessment of the knee.
There was no restriction of movements of ankle and knee in any of the patients in our study, in accordance with most other studies [18,19,25,26].
Lee et al demonstrated definite differences between donor and normal legs on gait analysis in his series of 10 patients of whom four underwent fibula head resection. He attributed this to weakness of deep muscles from loss of their normal origin and change in load transmission through the fibula [27].
Dieckmann et al reported high-stepping gait following resection of the common peroneal nerve for malignant lesions of the proximal fibula [21]. However, gait analysis failed to demonstrate significant differences in gait and motion of the knee in comparison to normal controls, in Draganich et al’s series of six patients, despite significant increase in knee ligament laxity [19]. Bickels et al reported 95% of normal gait function following Type I (marginal) resection and 77% of normal gait function following Type II (wide) resection [20].
None of the patients in our series had gait disturbance on clinical examination. This is likely to be due to the absence of malignant or aggressive lesions and hence the need for extensive dissection in our series. However quantitative analysis is likely to demonstrate gait affection even these patients as minor functional losses are not perceived by the patient or the examiner [28].
Though there have been reports of regeneration of the resected fibular shaft [11,26,29,30], to our knowledge there is no report of regeneration of the proximal third of fibula.
Bettin et al studied regeneration of the donor site in 53 patients undergoing transplantation of the fibular shaft and found age The scarcity of regeneration of the ends of the fibula can be understood with a detailed knowledge of the blood supply of the fibula and its periosteum. The lower third and majority of the upper third of fibula are subcutaneous and hence the periosteum relies more on the nutrient artery than on adjacent muscle arteries for its blood supply. When a fibular segment, the main source of blood supply to the periosteum is disrupted, and ischaemia of the periosteum leads to failure of regeneration of the fibular defect. In contrast, the middle third of the fibula which is richly surrounded by muscle origins has an abundance of muscle-periosteal anastomoses. With disruption of the nutrient artery through removal of a fibular segment, the muscle-periosteal anastomoses dilate and regeneration of the fibula is therefore more likely to occur [31].
Hsu et al and others have also reported on the higher regeneration potential at a younger age [26,31].  The unusual presence of proximal fibula regeneration in a single case in the present study is likely to be due to a favourable balance between interruption of the nutrient artery and the regeneration potential of the vessels and the periosteum at a younger age.
Though multiple authors [11,31-34] have reported proximal migration of fibula, ankle valgus deformity and/ or tibial diaphyseal valgus deformity of the tibia following resection of fibular shaft, little is known if such changes also occur following resection of the fibular head.
None of the patients in our series, including children, had any of the above changes. This could be because all patients had >50% of remnant fibula while only 10% of the fibula has been found to be essential distally to maintain ankle stability [35].

Conclusion

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Donor-site morbidity following simple and marginal resection of the proximal fibula is acceptable. Older patients appear to have a significantly higher risk of demonstrable clinical varus laxity. A longer follow-up would be required to determine if the asymptomatic instability would lead to early knee arthritis. Proximal fibula resection in children appears to be safe, though a larger study is warranted before the results are extrapolated to larger populations.

References

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1. Springfield D. Autograft reconstructions. Orthop Clin North Am 1996; 27:483-92.
2. Weiland AJ, Moore JR, Daniel RK. Vascularized bone autografts. Clin Orthop 1983; 174: 87–95.
3. Murray RA, Brindley HH. The proximal fibula: indications for excision and use. South Med J. 1957 Mar;50(3):297-302.
4. Murray JA, Schlafly B. Giant cell tumors in the distal end of the radius. Treatment by resection and fibular autograft interpositional arthroplasties. J Bone Joint Surg Am 1986;68:687-94.
5. Bassiony AA. Giant cell tumour of the distal radius: wide resection and reconstruction by non-vascularised proximal fibular autograft. Ann Acad Med Singapore. 2009 Oct;38(10):900-4.
6. Anderson AF, Green NE. Residual functional deficit after partial fibulectomy for bone grafts. Clin Orthop; 1991:137-140.
7. Draganich LF, Nicholas RW, Shuster JK, et al. The effects of resection of the proximal part of the fibula on stability of knee and on gait. J Bone Joint Surg (Am) 1991; 73: 575-583.
8. Bickels J, Kollender Y, Pritsch T, Meller I, Malawer MM. Knee stability after resection of the proximal fibula. Clin Orthop; 2006: 454:198–201.
9. Dieckmann R, Gebert C, Streitbürger A, Henrichs MP, Dirksen U, Rödl R, Gosheger G, Hardes J. Proximal fibula resection in the treatment of bone tumours. International Orthopaedics (SICOT). DOI 10.1007/s00264-010-1193-3.
10. Rettig A. Medial and lateral ligament injuries. In: Scott W, ed. Ligament and extensor mechanism injuries of the knee: Diagnosis and treatment. St. Louis, Mo:. Mosby;1991.
11. Herranz PG, Rio AD, Burgos J, Mondejar JAL, Rapariaz JM. Valgus deformity after fibular resection in children. J Paed Orthop 2003; 23:55-9.
12. Park HW, Kim HW, Kwak YH, Roh JY, Lee JJ, Lee KS. Ankle Valgus Deformity Secondary to Proximal Migration of the Fibula in Tibial Lengthening with Use of the Ilizarov External Fixator. J Bone Joint Surg Am. 2011;93:294-302.
13. Wang Q, Whittle M, Cunningham J, Kenwright J. Fibula and its ligaments in load transmission and ankle joint stability. Clin Orthop 1996; 330:261-70.
14. Lambert KL. The weight bearing function of the fibula. A strain gauge study. J Bone Joint Surg 1971;53-A:507–513.
15. Takebe K, Nakagawa A, Minami H, Kanazawa H, Hirohata K. Role of the fibula in weight-bearing. Clin. Orthop. 1984; 184: 289-292.
16. Goh JC, Mech AM, Lee EH, Ang EJ, Bayon P, Pho RW. Biomechanical study on the load-bearing characteristics of the fibula and the effects of fibular resection. Clin Orthop Relat Res. 1992; (279):223-228.
17. Grood ES, Noyes FR, Butler DL, Suntay WJ. Ligamentous and capsular restraints preventing straight medial and lateral laxity in intact human cadaver knees. J Bone and Joint Surg  1981;63-A: 1257-1269.
18. Youdas JW, Wood MB, Cahalan TD, et al. A quantitative analysis of donor site morbidity after vascularised fibular transfer. J Orthop Res 1988; 6:621-629.
19. Uchiyama E, Suzuki D, Kura H, Yamashita T, Murakami G. Distal fibular length needed for  ankle instability. Foot Ankle Int 2006; 27(3):185-9.
20. Babhulkar SS, Pande KC, Babhulkar S. Ankle instability after fibular resection. J Bone Joint Surg Br 1995; 77:258-61.
21. Pho RW. Malignant giant-cell tumor of the distal end of the radius treated by a free vascularized fibula transplant. J Bone Joint Surg Am 1981; 63:877-84.
22. Bird HA, Tribe CR, Bacon PA. Joint hypermobility leading to osteoarthrosis and chondrocalcinosis. Annals of the Rheumatic Diseases; 1978: 37:203-211.
23. Kannus P. Long-term results of conservatively treated medial collateral ligament injuries of the knee joint. Clin Orthop1988;226:103–12.
24. Kannus P. Nonoperative treatment of grade II and III sprains of the lateral ligament compartment of the knee. Am J Sports Med1989;17:83–8.
25. Gore DR, Gardner GM, Sepic SB, et al. Function following partial fibulectomy. Clin Orthop 1987; 220:206-10.
26. Bettin D, Böhm H, Clatworthy M, Zurakowski D, Link TM. Regeneration of the donor side after autogenous fibula transplantation in 53 patients. Acta Orthopaedica; 2003; 74(3): 332-336.
27. Lee EH, Goh JCH. Helm R, et al. Donor site morbidity following resection of the fibula. J Bone Joint Surg 1990; 72B: 129-131.
28. Bodde EW, Visser ED, Duysens JEJ, Harman EHM. Donor site morbidity after free vascularized fibular transfer; Subjective and Quantitative analysis. Plast Reconstr Surg 2003; 11: 2237-42.
29. Edelman R, Barbacci, D. Fibular regeneration. J Foot Surg; 1992; 3 1 (49): 368-71.
30. Vandeweyer E, Gebhart M. Complete fibular regeneration following removal of the fibula for bone grafting. Acta Chir Belg 1996; 96(4):182-4.
31. Hsu LC, Yau AC, O’Brien JP,  et al. Valgus deformity of the ankle resulting from fibular resection for a graft in subtalar fusion in children. J Bone Joint Surg (Am) 1972; 54:585-94.
32. Wiltse LL. Valgus deformity of the ankle: A sequel to acquired or congenital abnormalities of the fibula. J Bone Joint Surg (Am) 1972; 54:595-606.
33. Kanaya K, Wada T, Kura H,  Yamashita T, Usui M, Ishii S. Valgus deformity of the ankle following harvesting of a vascularized fibular graft in children. J Reconstr Microsurg 2002: 18(2):91-6.
34. Fragniere B, Wicart P, Mascard E, Dubousset J. Prevention of ankle valgus after vascularized fibular grafts in children. Clin Orthop 2003; 408:245-51.
35. Pacelli LL, Gillard J, McLoughlin SW, Buehler MJ. Biomechanical analysis of donor-site ankle instability following free fibular graft harvest. J Bone Joint Surg (Am) 2003; 85-A (4):597-603.

Source(s) of Funding

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Competing Interests

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