OBJECTIVE: To investigate the efficacy of minimally invasive osteotomy with preservation of blood supply to the transversely transported bone segment in the treatment of chronic ischemic lower limb diseases using tibial transverse bone transport. METHODS: A retrospective analysis was conducted on the clinical data of 12 patients with chronic ischemic lower limb diseases who met the selection criteria and were treated between June 2016 and December 2023. The cohort included 7 males and 5 females, aged 26-87 years (mean, 61.2 years). Among them, 7 patients had diabetic foot (DF), including 2 cases complicated by arteriosclerosis obliterans (ASO), with a DF duration ranging from 1.7 to 23.0 months (mean, 9.6 months) and ulcer sizes ranging from 3.2 cm×2.4 cm to 10.0 cm×6.6 cm. Three patients had ASO with a disease duration of 1.7-23.0 months (mean, 10.4 months) and ulcer or post-amputation wound sizes ranging from 2.2 cm×2.1 cm to 12.0 cm×7.7 cm. Additionally, 2 patients with thromboangiitis obliterans (TAO) had a disease duration of 7 and 12 months, respectively. Preoperatively, the mean foot skin temperature was (27.63±0.34)℃, and the visual analogue scale (VAS) score was 8.5±0.7. All patients underwent tibial transverse bone transport using minimally invasive osteotomy while preserving the blood supply to the transported bone segment. Postoperative complications and foot ulcer healing were observed. The effectiveness of tibial transverse bone transport was evaluated by comparing preoperative and postoperative foot skin temperature, VAS scores, as well as through CT angiography (CTA). RESULTS: One DF patient with ASO was lost to follow-up, while the remaining 11 patients were followed up 10-29 months (mean, 20.5 months). One DF patient had a displaced fracture at the site of tibial transport due to trauma, which healed after plaster immobilization; 1 DF patient had a small amount of pigmentation in the skin of the donor site, but the blood circulation was good; no complication such as pin tract infection, skin necrosis, or osteomyelitis occurred in the donor site of all patients. At 2-3 weeks postoperatively, the foot skin temperature was (34.21±0.65)℃, and the VAS score was 0.3±0.1, both significantly improved compared to preoperative ones ( t=-31.578, P<0.001; t=49.000, P<0.001). Two TAO patients experienced recurrent, persistent, intolerable pain at 7-10 days postoperatively, with no reduction in ulcer size or necrotic areas; 1 underwent toe amputation, and the other required a mid-leg amputation. The remaining patients achieved complete ulcer healing, with healing time ranging from 5.1 to 9.2 weeks (mean, 6.8 weeks). CTA showed no new vascular occlusions or embolisms. X-ray films at 4 months postoperatively demonstrated proper repositioning and good healing of the transported tibial bone segment. CONCLUSION The application of minimally invasive osteotomy with preserved blood supply to the transversely transported bone segment in tibial transverse bone transport for the treatment of chronic ischemic lower limb diseases effectively minimizes extensive soft tissue dissection, reduces surgical soft tissue damage, and better maintains local blood supply. This approach lowers the risk of postoperative infection and skin necrosis while accelerating postoperative recovery.
Humans ; Osteotomy/methods* ; Middle Aged ; Male ; Female ; Aged ; Tibia/surgery* ; Minimally Invasive Surgical Procedures/methods* ; Retrospective Studies ; Adult ; Bone Transplantation/methods* ; Aged, 80 and over ; Diabetic Foot/surgery* ; Treatment Outcome ; Arteriosclerosis Obliterans/surgery* ; Ischemia/surgery* ; Lower Extremity/blood supply*

OBJECTIVE: To investigate the effect of femoral condyle sliding osteotomy (FCSO) on the flexion gap and external rotation of the prosthesis in balancing coronal instability during initial total knee arthroplasty (TKA). METHODS: Between November 2021 and October 2024, FCSO technique was applied to balance the coronal medial and lateral spaces during initial TKA in 3 patients, including medial condyle sliding osteotomy (MCSO) and lateral condyle sliding osteotomy (LCSO). There were 1 male and 2 females with the age of 81, 68, and 68 years old. The affected knee has varus or valgus deformity, with tibia-femoral angles of 169.7°, 203.3°, and 162.2°, respectively. The hip-knee-ankle angle (HKA), range of motion (ROM), knee society scoring system (KSS), and pain visual analogue scale (VAS) score were used to evaluate joint function and pain relief. Based on model bone, the thickness and bone bed area of the medial and lateral femoral condyle osteotomy blocks in FCSO were measured. During TKA in 12 patients, the range of osteotomy block movement was evaluated. By simplifying the upward and forward movement of the osteotomy block into a geometric model, the impact of movement on the flexion gap and external rotation of the prosthesis was calculated. RESULTS: After application of FCSO during TKA, the limb alignment and medial and lateral balance at extension and flexion positions were restored in 3 patients. Three patients were followed up 23, 11, and 3 months, respectively. Postoperative HKA, pain VAS score, KSS score, and ROM all showed significant improvement compared to preoperative levels. The maximum thickness of osteotomy blocks by MCSO and LCSO was 17 and 12 mm, respectively. The simple upward movement of the osteotomy block mainly affected the extension gap, and had little effect on the flexion gap and external rotation of the prosthesis. Moving the osteotomy block forward at the same time had a significant impact on the flexion gap and external rotation of the prosthesis, especially on LCSO. Mild forward movement leaded to a decrease in external rotation of more than 3°, which had a serious impact on the patellar trajectory. CONCLUSION FCSO can effectively solve the problem of imbalance between the medial and lateral spaces during initial TKA, avoiding knee joint instability caused by excessive loosening and limiting the use of constrained condylar prosthesis. The distance for the downward movement of the osteotomy block in MCSO and LCSO was 3-5 mm and 6-8 mm, respectively, with 10-15 mm of space for forward movement and almost no space for backward movement. For MCSO, the upward and forward movement of the osteotomy block will increase the external rotation of the prosthesis, which is beneficial for improving the patellar trajectory and suitable for valgus knee. LCSO is suitable for varus knee, and the osteotomy block only slides vertically up and down without moving forward and backward.
Humans ; Osteotomy/methods* ; Male ; Female ; Arthroplasty, Replacement, Knee/methods* ; Aged ; Range of Motion, Articular ; Femur/surgery* ; Knee Joint/physiopathology* ; Aged, 80 and over ; Knee Prosthesis ; Treatment Outcome ; Osteoarthritis, Knee/surgery*

OBJECTIVE: To explore the effectiveness of triple osteotomy in correcting severe hallux valgus with the first metatarsal pronation deformity. METHODS: A retrospective analysis was conducted on the clinical data of 29 patients (40 feet) with severe hallux valgus accompanied by the first metatarsal pronation deformity, who were admitted between January 2022 and December 2023 and met the selection criteria. There were 8 males (10 feet) and 21 females (30 feet), with an average age of 50.0 years (range, 44-62 years). The disease duration ranged from 5 to 9 years (mean, 6.5 years). All patients underwent triple osteotomy to correct the deformity. The American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS) score were used to evaluate joint function and pain before and after operation. Based on pre- and post-operative X-ray films, hallux valgus angle (HVA), intermetatarsal angle (IMA), and distal metatarsal articular angle (DMAA) were measured to evaluate the correction of hallux valgus; the shape classification of the lateral edge of the first metatarsal and the pronation of first metatarsal angle (PFMA) were observed to assess the correction of the first metatarsal pronation deformity. RESULTS: A superficial infection occurred in 1 foot and the incison healed after dressing change; the remaining incisions healed by first intention. All patients were followed up 12-18 months (mean, 12.6 months). Three cases (4 feet) experienced limited movement of the metatarsophalangeal joint after operation, and the joint function recovered after strengthening functional exercises. During follow-up, no recurrence of deformity or secondary metatarsal pain occurred. Compared with preoperative scores, the AOFAS score increased and the VAS score decreased at last follow-up, and the differences were significant ( P<0.05). Radiographic examination showed that the osteotomy achieved bony healing, with the healing time of 2.5-6.2 months (mean, 4.1 months). The hallux valgus deformity was corrected, and the IMA, HVA, and DMAA were significantly smaller at last follow-up when compared with those before operation ( P<0.05). The first metatarsal pronation deformity was also corrected; there was no R-type (R-type for pronation deformity) on the lateral edge of the first metatarsal at last follow-up, and the PFMA decreased compared with preoperative levels ( P<0.05) and was corrected to the normal range. CONCLUSION Triple osteotomy can achieve good effectiveness for correcting severe hallux valgus with the first metatarsal pronation deformity. The functional training of the first metatarsophalangeal joint needs to be strengthened.
Humans ; Hallux Valgus/diagnostic imaging* ; Osteotomy/methods* ; Female ; Male ; Middle Aged ; Adult ; Retrospective Studies ; Metatarsal Bones/diagnostic imaging* ; Treatment Outcome ; Pronation ; Radiography

OBJECTIVE: To explore the effectiveness of QIN Sihe's surgical strategy combined with Ilizarov technique in treating foot and ankle deformities on the verge of amputation. METHODS: A retrospective analysis was conducted on the clinical data of 56 patients (62 feet) with foot and ankle deformities on the verge of amputation treated with QIN Sihe's surgical strategy and Ilizarov technique between May 2010 and December 2020. Among them, there were 39 males and 17 females. The age ranged from 8 to 62 years (median, 27.5 years). QIN Sihe's surgical strategy: subcutaneous release or open lengthening of contracted Achilles tendons, limited correction of bony deformities through multiple osteotomies during surgery, tendon transfer to balance the power of the foot and ankle, simultaneous percutaneous osteotomy and correction of tibial torsion deformity to restore the weight-bearing line of the lower extremity, and installation of Ilizarov foot and ankle distraction devices for slow distraction and correction of residual foot and ankle deformities. After removal of external fixation, individualized braces were used for protection during exercise and walking. For patients with bilateral deformities, staged surgeries were performed. The effectiveness was evaluated according to the QIN Sihe's Postoperative Evaluation Criteria for Lower Limb (Foot and Ankle) Deformity Correction and Functional Reconstruction at last follow-up. RESULTS: All patients achieved the preoperative expected orthopedic and functional reconstruction goals. The postoperative wearing time of external fixator was 3-7 months, with an average of 5.5 months. The incidence of pin tract infection during the treatment period was 6.5% (4/62). All patients were followed up 25-132 months (median, 42 months). All 56 patients successfully retained their limbs. At last follow-up, foot and ankle deformities were corrected, the weight-bearing line was basically restored, and plantigrade feet were restored. At last follow-up, according to QIN Sihe's Postoperative Evaluation Criteria for Lower Limb (Foot and Ankle) Deformity Correction and Functional Reconstruction, the effectiveness was rated as excellent in 37 cases (39 feet), good in 18 cases (21 feet), and fair in 1 case (2 feet). The excellent and good rate was 96.8% (60/62). CONCLUSION The combination of QIN Sihe's surgical strategy and Ilizarov technique in treating foot and ankle deformities on verge of amputation is minimally invasive, safe, and the therapeutic effect is controllable. This combined approach has unique advantages in preserving limb function and restoring biomechanical balance.
Humans ; Ilizarov Technique ; Male ; Female ; Retrospective Studies ; Adult ; Middle Aged ; Adolescent ; Child ; Young Adult ; Amputation, Surgical ; Osteotomy/methods* ; Ankle/surgery* ; Treatment Outcome ; Foot Deformities/surgery* ; Tendon Transfer/methods* ; Achilles Tendon/surgery* ; Foot/surgery*

OBJECTIVE: To summarize the clinical characteristics of foot and ankle deformities combined with knee and lower limb deformities and evaluate the advantages, clinical outcomes, and considerations of QIN Sihe's surgical strategy for treating such complex deformities. METHODS: Between January 2022 and December 2024, 32 patients with foot and ankle deformities combined with knee and lower limb deformities were enrolled. The cohort included 23 males and 9 females, aged 10-67 years (mean, 41.1 years). The main etiologies included post-polio sequelae (20 cases) and congenital limb deformities (3 cases). Deformities were categorized as follows: equinovarus foot (12 cases), equinus foot (2 cases), equinovalgus foot (3 cases), equinus foot with swan-neck deformity (2 cases), calcaneus foot (5 cases), foot valgus (2 cases), knee flexion deformity (14 cases), genu recurvatum (4 cases), genu varum (3 cases), genu valgum (3 cases), lower limb shortening (3 cases), and lower limb external rotation (6 cases). QIN Sihe's surgical strategies included osteotomies, tendon releases, and tendon transfers for deformity correction, followed by external fixation for residual deformity adjustment and stabilization. Outcomes were assessed using QIN Sihe's Postoperative Evaluation Criteria for Lower Limb (Foot and Ankle) Deformity Correction and Functional Reconstruction. RESULTS: All patients were followed up 8-32 months (mean, 16.5 months). Complications included pin tract infection (1 case, 1 site), ankle pain (2 cases), delayed healing at the proximal tibial osteotomy site (1 case), and anterior talar dislocation (1 case). At last follow-up, insufficient correction of foot deformity was observed in 1 case; both knee and lower limb deformities were corrected, with only mild recurrence of knee flexion deformity in 1 case. The foot/ankle and knee joint function improved. Based on QIN Sihe's Postoperative Evaluation Criteria for Lower Limb (Foot and Ankle) Deformity Correction and Functional Reconstruction, outcomes were rated as excellent in 30 cases and good in 2 cases, with an excellent-good rate of 100%. CONCLUSION Foot and ankle deformities combined with knee and lower limb deformities are complex, QIN Sihe's surgical strategy can achieve satisfactory clinical outcomes for simultaneous correction.
Humans ; Male ; Female ; Adult ; Middle Aged ; Child ; Adolescent ; Aged ; Treatment Outcome ; Young Adult ; Plastic Surgery Procedures/methods* ; Lower Extremity Deformities, Congenital/surgery* ; Osteotomy/methods* ; Foot Deformities, Congenital/surgery* ; Ankle Joint/surgery* ; Knee Joint/surgery* ; Foot Deformities/surgery*

OBJECTIVE: To evaluate the effectiveness of correcting post-traumatic equinovarus deformity using Ilizarov external fixation technique combined with limited osteotomy. METHODS: A retrospective analysis was conducted on clinical data from 29 patients with post-traumatic equinovarus deformity treated between July 2018 and March 2023. The cohort included 18 males and 11 females, with ages ranging from 15 to 57 years (mean, 24.3 years). All patients exhibited ankylosed ankle joints with equinovarus deformity. During surgery, external fixators were installed according to Ilizarov pinning principles, and minimally invasive osteotomy was performed at the ankle joint. Concurrently, soft tissue release was achieved via minimally invasive Achilles tendon lengthening. Postoperatively, multiplanar deformity correction was accomplished through gradual adjustment of the external fixator. The fixator was removed after bony union at the osteotomy site, followed by bracing. The surgical duration, intraoperative blood loss, fixator wear time, and complications were recorded. Postoperative outcomes included assessment of deformity correction and bony union at the osteotomy site. Functional improvement and pain relief were evaluated using pre- and post-operative scores from the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score and visual analogue scale (VAS) score. RESULTS: All 29 patients were followed up 12-24 months (mean, 18 months). The mean surgical duration was 85.6 minutes, with a mean intraoperative blood loss of 110 mL. Full deformity correction was achieved within 26-80 days (mean, 40.7 days) through progressive fixator adjustments. At correction completion, all ankles restored to a neutral or 5°-10° dorsiflexed position with plantigrade foot function. Superficial pin tract infections occurred in 3 patients (10.3%), resolved with local wound care, enhanced nursing, and oral antibiotics. No deep or systemic infections was observed. One patient sustained a calcaneal half-pin fracture due to a fall during fixator wear, but no bone fragment displacement occurred. No vascular or neurological complication was reported. Complete bony union was achieved at all osteotomy sites without nonunion. At last follow-up, the AOFAS ankle-hindfoot score improved from preoperative 42.7±8.7 to postoperative 65.7±9.3, and the VAS score decreased from preoperative 4.5±1.3 to postoperative 2.5±1.1, with significant differences ( P<0.05). Functional outcomes were rated as excellent in 14 cases, good in 13 cases, fair in 1 case, and poor in 1 case, with an excellent and good rate of 93.1%. CONCLUSION The progressive correction strategy combining Ilizarov external fixation technique with limited foot osteotomy effectively corrects post-traumatic equinovarus deformity while preserving soft tissue integrity. This method is associated with minimal, largely controllable complications and achieves alignment stability and fusion outcomes comparable to traditional open surgery, making it an effective treatment for complex foot and ankle deformities.
Humans ; Male ; Female ; Osteotomy/methods* ; Adult ; Retrospective Studies ; Ilizarov Technique ; Middle Aged ; Adolescent ; External Fixators ; Young Adult ; Treatment Outcome ; Ankle Joint/surgery* ; Clubfoot/etiology* ; Minimally Invasive Surgical Procedures/methods*

OBJECTIVE: To evaluate the functional and aesthetic evaluation of external fixator lengthening through plantar approach for fourth brachymetatarsia. METHODS: A retrospective analysis was conducted on 20 patients (23 feet) with fourth brachymetatarsia who met the selection criteria between January 2016 and January 2024, including 3 males and 17 females, with 8 left, 9 right, and 3 bilateral cases. The mean age was 24.7 years (range, 14-51 years). The preoperative metatarsal shortening length was (13.8±3.2) mm. The preoperative American Orthopaedic Foot and Ankle Society (AOFAS) forefoot score was 79.5±3.9, the visual analogue scale (VAS) score of appearance satisfaction was 1.7±0.8, and the appearance index (AI) score was 13.6±0.9. All patients underwent external fixator lengthening through plantar approach. The lengthening length of metatarsal bone, lengthening ratio, healing time, and healing index were recorded. Functional outcomes were assessed using the AOFAS forefoot score, VAS score of appearance satisfaction, and quality-of-life impact with AI questionnaire. RESULTS: All 20 patients were followed up 14-55 months with an average of 36.3 months. During the follow-up, complications occurred in 4 cases (17.4%), including 2 cases of metatarsophalangeal joint stiffness, which had no significant effect on the function and appearance. Delayed union of osteotomy occurred in 1 case (healed at 12 weeks after operation). Pin loosening occurred in 1 case and recovered after outpatient reinforcement. No complications related to plantar scar occurred. At last follow-up, the lengthening length of metatarsal bone was (13.9±3.1) mm, and the lengthening ratio was 25.8%±5.6%. All cases achieved bony union, with a mean healing time of (64.3±12.5) days and a healing index of (46.9±4.8) d/cm. At last follow-up, AOFAS score was 98.9±2.1, the VAS score of appearance satisfaction was 9.3±0.7, and the AI score was 0.6±0.8, which significantly improved when compared with those before operation ( t=27.398, P<0.001; t=32.994, P<0.001; t=56.135, P<0.001). CONCLUSION External fixator lengthening through plantar approach is a safe and effective technique for fourth brachymetatarsia, achieving satisfactory functional and aesthetic outcomes.
Humans ; Male ; Female ; Adult ; External Fixators ; Retrospective Studies ; Bone Lengthening/instrumentation* ; Middle Aged ; Metatarsal Bones/abnormalities* ; Adolescent ; Young Adult ; Treatment Outcome ; Patient Satisfaction ; Esthetics ; Osteotomy/methods* ; Foot Deformities, Congenital/surgery*

OBJECTIVE: To investigate the management strategies of external fixation combined with microsurgical techniques for repairing complex foot and ankle wounds in children. METHODS: The clinical data of 9 children with complex foot and ankle wounds who met the selection criteria between June 2017 and December 2021 was retrospectively analyzed. There were 6 boys and 3 girls, aged 3-13 years, with an average of 7.4 years. The causes of injury included crush injury in 5 cases and traffic accident injury in 4 cases. The wound size ranged from 6 cm×5 cm to 25 cm×18 cm. The time from injury to surgery ranged from 3 to 8 hours, with an average of 5 hours. All cases underwent staged surgical treatment. Among the 3 cases requiring deformity correction, 2 cases initially underwent free anterolateral thigh flap transplantation for wound coverage and limb salvage, followed by circular external fixation combined with osteotomy to address postoperative limb deformity, while 1 case received osteotomy for tibial fracture realignment prior to local pedicled flap reconstruction. All the 6 cases with non-deformity correction underwent initial external fixation followed by secondary flap reconstruction for wound management. The American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot score was used to evaluate the foot and ankle function of children. RESULTS: All children successfully achieved limb salvage postoperatively. Among the 6 non-deformity correction cases, all flaps survived with satisfactory wound healing and no infection was observed; fractures healed within 2.5-4.5 months, after which external fixators were removed for functional rehabilitation with favorable recovery. One case treated with circular external fixation combined with osteotomy achieved bone union at 4 months postoperatively, followed by fixator removal. One case undergoing osteotomy for tibial fracture realignment showed bone healing at 2.5 months post-correction, with subsequent fixator removal. One patient receiving bone lengthening developed infection at 1 week postoperatively, which was managed with multiple debridements, ultimately achieving bone union at 16 months postoperatively and followed by fixator removal. At last follow-up, all patients demonstrated satisfactory ankle-hindfoot functional recovery, with AOFAS ankle-hindfoot scores ranging from 80 to 90 (mean, 84.2). CONCLUSION The combination of external fixation and microsurgical techniques demonstrates significant advantages in reconstructing complex foot and ankle wounds in children. The synergistic interaction provides both mechanical stability and biological repair, enabling early functional rehabilitation while reducing infection risks.
Humans ; Child ; Male ; Female ; Adolescent ; Child, Preschool ; Foot Injuries/surgery* ; Ankle Injuries/surgery* ; Retrospective Studies ; External Fixators ; Microsurgery/methods* ; Plastic Surgery Procedures/methods* ; Surgical Flaps ; Fracture Fixation/methods* ; Osteotomy/methods* ; Treatment Outcome

Severe hallux valgus, a triplanar foot deformity significantly impairing patients' quality of life, has witnessed progressive advancements in surgical management. This article systematically reviews the therapeutic progress through literature analysis, encompassing modifications of conventional surgical procedures and applications of novel techniques and innovative biomaterials. A critical analysis and discussion of these technological advancements and future developmental directions are presented to provide valuable insights and references for clinical management of severe hallux valgus.
Humans ; Hallux Valgus/surgery* ; Osteotomy/methods* ; Bone Transplantation/methods* ; Orthopedic Procedures/methods*

OBJECTIVE: To investigate the effectiveness of basal osteotomy of the first metatarsal combined with first metatarsophalangeal joint replacement for the treatment of hallux valgus combined with hallux rigidus. METHODS: A retrospective analysis was conducted on the medical records of 15 patients (16 feet) with hallux valgus combined with hallux rigidus who underwent first metatarsal basal osteotomy combined with first metatarsophalangeal joint replacement between May 2019 and December 2024. The patients included 1 male and 14 females, aged 60-80 years, with an average age of 68.5 years. According to the Mann classification of hallux valgus, 2 feet were moderate and 14 feet were severe. According to the Hallux Rigidus Coughlin grading, 12 feet were grade 3 and 4 feet were grade 4. The evaluation indicators included hallux valgus angle (HVA) and intermetatarsal angle (IMA) measured on weight-bearing X-ray film at preoperation and last follow-up; the American Orthopaedic Foot and Ankle Society (AOFAS) score and visual analogue scale (VAS) score were used to evaluate the improvement of walking function, metatarsophalangeal joint function, and pain relief in patients. RESULTS: All patients underwent surgery successfully without complications such as vascular or nerve injury during operation. One foot developed a superficial incisional infection postoperatively, which healed after dressing changes; the remaining 15 feet had primary incision healing. All patients were followed up 5-55 months, with an average of 17.5 months. All osteotomies achieved bony union, with a union time ranging from 8 to 13 weeks, averaging 11.8 weeks; no elevation of the first metatarsal was observed. At last follow-up, no complications such as prosthesis loosening, dislocation, fracture, toe shortening, bone dissolution, synovial reaction, or metatarsalgia was found. The appearance and function of the affected feet significantly improved, and the pain significantly relieved. At last follow-up, the HVA, IMA, AOFAS score, and VAS score showed significant differences when compared with preoperative values ( P<0.05). CONCLUSION Basal osteotomy of the first metatarsal combined with first metatarsophalangeal joint replacement for the treatment of hallux valgus with hallux rigidus can correct deformities through osteotomy, restore the normal flexion-extension axis of the metatarsophalangeal joint, relieve pain, and preserve a certain degree of mobility, achieving good short- and mid-term effectiveness.
Humans ; Male ; Female ; Hallux Valgus/diagnostic imaging* ; Osteotomy/methods* ; Aged ; Middle Aged ; Metatarsophalangeal Joint/surgery* ; Retrospective Studies ; Hallux Rigidus/diagnostic imaging* ; Aged, 80 and over ; Metatarsal Bones/surgery* ; Treatment Outcome ; Arthroplasty, Replacement/methods*