Three-Year Rates of Reoperation and Revision Following Mobile Versus Fixed-Bearing Total Ankle Arthroplasty: A Cohort of 302 Patients with 2 Implants of Similar Design

BACKGROUND

Currently, the implants utilized in total ankle arthroplasty (TAA) are divided between mobile-bearing 3-component and fixed-bearing 2-component designs. The literature evaluating the influence of this mobility difference on implant survival is sparse. The purpose of the present study was therefore to compare the short-term survival of 2 implants of similar design from the same manufacturer, surgically implanted by the same surgeons, in fixed-bearing or mobile-bearing versions.

METHODS

All patients were enrolled who underwent TAA with either the mobile-bearing Salto (Tornier and Integra) or the fixed-bearing Salto Talaris (Integra) in 3 centers by 2 surgeons between January 2004 and March 2018. All patients who underwent TAA from January 2004 to April 2013 received the Salto implant, and all patients who underwent TAA after November 2012 received the Salto Talaris implant. The primary outcome was time, within 3 years, to first all-cause reoperation, revision of any metal component, and revision of any component, including the polyethylene insert. Secondary outcomes included the frequency, cause, and type of reoperation.

RESULTS

A total of 302 consecutive patients were included, of whom 171 received the mobile-bearing and 131 received the fixed-bearing implant. The adjusted hazard ratio for all-cause reoperation was 1.42 (95% confidence interval [CI], 0.67 to 3.00; p = 0.36); for component revision, 3.31 (95% CI, 0.93 to 11.79; p = 0.06); and for metal component revision, 2.78 (95% CI, 0.58 to 13.33; p = 0.20). A total of 31 reoperations were performed in the mobile-bearing group compared with 14 in the fixed-bearing group (p = 0.07). More extensive reoperation procedures were performed in the mobile-bearing group.

CONCLUSIONS

With the largest comparison of 2 implants of similar design from the same manufacturer, the present study supports the use of a fixed-bearing design in terms of short-term failure. We found a 3-times higher rate of revision among mobile-bearing implants compared with fixed-bearing implants at 3 years after TAA. Reoperations, including first and subsequent procedures, tended to be less common and the causes and types of reoperations less extensive among fixed-bearing implants.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Outcome of the modified Lapidus procedure for hallux valgus deformity during the first year following surgery: A prospective clinical and gait analysis study

BACKGROUND

The modified Lapidus procedure is a surgical option to treat moderate to severe hallux valgus deformity with good radio-clinical outcome. However, comprehensive biomechanical outcome evaluation of this surgery at mid-term follow-up is missing. This study assesses and compares the radio-clinical and gait outcome at 6 and 12 months following modified Lapidus procedure.

METHOD

Ten consecutive female patients with moderate to severe hallux valgus who underwent modified Lapidus procedure participated in the study. Comprehensive gait assessment was performed preoperatively, at 6 and 12 months postoperatively. Gait parameters including spatiotemporal, kinematics and plantar pressure were analyzed using pressure insoles and 3-dimensional inertial sensors. Outcome was evaluated using two clinical questionnaires, i.e. the American Orthopaedic Foot and Ankle Score and the Foot and Ankle Ability Measure, and X-rays.

FINDINGS

Three spatiotemporal, two kinematics, and seven plantar pressure parameters significantly improved between 6 months and 12 months postoperatively. Significant improvement in radiological and clinical outcome was reported at 6 and 12 months. The Foot and Ankle Ability Measure showed non-significant improvement at 12 months.

INTERPRETATION

The outcome of this study is consistent with the previously reported good clinical and radiological results at one year following Lapidus for moderate to severe hallux valgus. Twelve gait parameters demonstrated that outcome improves from 6 months to 12 months postoperative with room for further improvement at long term. The gait outcome in this study confirms the longer rehabilitation period following modified Lapidus procedure. Studies with a larger sample size are required to confirm these findings.

Comparison of peripheral nerve blockade characteristics between non-diabetic patients and patients suffering from diabetic neuropathy: a prospective cohort study

Animal data have demonstrated increased block duration after local anaesthetic injections in diabetic rat models. Whether the same is true in humans is currently undefined. We, therefore, undertook this prospective cohort study to test the hypothesis that type-2 diabetic patients suffering from diabetic peripheral neuropathy would have increased block duration after ultrasound-guided popliteal sciatic nerve block when compared with patients without neuropathy. Thirty-three type-2 diabetic patients with neuropathy and 23 non-diabetic control patients, scheduled for fore-foot surgery, were included prospectively. All patients received an ultrasound-guided popliteal sciatic nerve block with a 30 ml 1:1 mixture of lidocaine 1% and bupivacaine 0.5%. The primary outcome was time to first opioid request after block procedure. Secondary outcomes included the time to onset of sensory blockade, and pain score at rest on postoperative day 1 (numeric rating scale 0-10). These outcomes were analysed using an accelerated failure time regression model. Patients in the diabetic peripheral neuropathy group had significantly prolonged median (IQR [range]) time to first opioid request (diabetic peripheral neuropathy group 1440 (IQR 1140-1440 [180-1440]) min vs. control group 710 (IQR 420-1200 [150-1440] min, p = 0.0004). Diabetic peripheral neuropathy patients had a time ratio of 1.57 (95%CI 1.10-2.23, p < 0.01), experienced a 59% shorter time to onset of sensory blockade (median time ratio 0.41 (95%CI 0.28-0.59), p < 0.0001) and had lower median (IQR [range]) pain scores at rest on postoperative day 1 (diabetic peripheral neuropathy group 0 (IQR 0-1 [0-5]) vs. control group 3 (IQR 0-5 [0-9]), p = 0.001). In conclusion, after an ultrasound-guided popliteal sciatic nerve block, patients with diabetic peripheral neuropathy demonstrated reduced time to onset of sensory blockade, with increased time to first opioid request when compared with patients without neuropathy.

Subjective versus objective assessment in early clinical outcome of modified Lapidus procedure for hallux valgus deformity

BACKGROUND

Studies have assessed the outcome of hallux valgus surgeries based on subjective questionnaires, usually the American Orthopaedic Foot and Ankle Society Score, and radiographic results reporting good to excellent outcome at 6-12 months postoperatively. However, contrasting results were reported by gait studies at 12-24 months postoperatively. In a previous study, we found nine gait parameters which can describe the altered gait in hallux valgus deformity. This study aimed, to assess the outcome of modified Lapidus at 6 months postoperatively, using gait assessment method, to determine if the nine specified gait parameters effectively relates with the clinical scores and the radiological results or add information missed by these commonly used clinical assessments.

METHOD

We assessed 21 participants including 11 controls and 10 patients with moderate to severe hallux valgus deformity. The patient group was followed 6 months postoperatively. The ambulatory gait assessment was performed utilizing pressure insoles and inertial sensors. Clinical assessment includes foot and ankle questionnaires along with radiographic results. Comparison was made using non parametric tests, P<0.05.

FINDINGS

Altered gait patterns, similar to the preoperative outcome, persisted at 6 months postoperatively when compared to controls. The foot and ankle ability measure score showed an outcome comparable to the gait results. In contrast, the American Orthopaedic Foot and Ankle Society Score and radiographic results showed significant improvement.

INTERPRETATION

Study supports the reliability of nine defined gait parameters in assessing the outcome of hallux valgus surgeries. The existing clinical assessment overestimates the functional outcome at the early postoperative phase.

Characterization of gait in female patients with moderate to severe hallux valgus deformity

BACKGROUND

Hallux valgus is one of the most common forefoot problems in females. Studies have looked at gait alterations due to hallux valgus deformity, assessing temporal, kinematic or plantar pressure parameters individually. The present study, however, aims to assess all listed parameters at once and to isolate the most clinically relevant gait parameters for moderate to severe hallux valgus deformity with the intent of improving post-operative patient prognosis and rehabilitation.

METHODS

The study included 26 feet with moderate to severe hallux valgus deformity and 30 feet with no sign of hallux valgus in female participants. Initially, weight bearing radiographs and foot and ankle clinical scores were assessed. Gait assessment was then performed utilizing pressure insoles (PEDAR) and inertial sensors (Physilog) and the two groups were compared using a non-parametric statistical hypothesis test (Wilcoxon rank sum, P<0.05). Furthermore, forward stepwise regression was used to reduce the number of gait parameters to the most clinically relevant and correlation of these parameters was assessed with the clinical score.

FINDINGS

Overall, the results showed clear deterioration in several gait parameters in the hallux valgus group compared to controls and 9 gait parameters (effect size between 1.03 and 1.76) were successfully isolated to best describe the altered gait in hallux valgus deformity (r(2)=0.71) as well as showed good correlation with clinical scores.

INTERPRETATION

Our results, and nine listed parameters, could serve as benchmark for characterization of hallux valgus and objective evaluation of treatment efficacy.

[Diagnosis and treatment of the ruptured Achilles tendon]

The treatment of the recently ruptured Achilles tendon can be conservative or surgical. The conservative treatment may be carried out using either a static cast immobilisation or using a dynamic brace and an early functional rehabilitation. The surgical technique can be either open or mini-invasive. Neglected and ancient ruptures may need to be treated surgically by a tendinoplasty. There is an ongoing discussion about how to manage the recently ruptured Achilles tendon, especially since recent descriptions of conservative-functional treatment procedures and mini-invasive surgical techniques. We present the choice of the different treatment options and the clinical reasoning to identify the best adapted treatment for the individual patient. The ideal treatment option depends on the functional demand and the medical condition of the patient.

Multi-segment foot kinematics after total ankle replacement and ankle arthrodesis during relatively long-distance gait

This study aimed to investigate the influence of ankle osteoarthritis (AOA) treatments, i.e., ankle arthrodesis (AA) and total ankle replacement (TAR), on the kinematics of multi-segment foot and ankle complex during relatively long-distance gait. Forty-five subjects in four groups (AOA, AA, TAR, and control) were equipped with a wearable system consisting of inertial sensors installed on the tibia, calcaneus, and medial metatarsals. The subjects walked 50-m twice while the system measured the kinematic parameters of their multi-segment foot: the range of motion of joints between tibia, calcaneus, and medial metatarsals in three anatomical planes, and the peaks of angular velocity of these segments in the sagittal plane. These parameters were then compared among the four groups. It was observed that the range of motion and peak of angular velocities generally improved after TAR and were similar to the control subjects. However, unlike AOA and TAR, AA imposed impairments in the range of motion in the coronal plane for both the tibia-calcaneus and tibia-metatarsals joints. In general, the kinematic parameters showed significant correlation with established clinical scales (FFI and AOFAS), which shows their convergent validity. Based on the kinematic parameters of multi-segment foot during 50-m gait, this study showed significant improvements in foot mobility after TAR, but several significant impairments remained after AA.

Outcome evaluation of ankle osteoarthritis treatments: plantar pressure analysis during relatively long-distance walking

BACKGROUND

This study aimed to use plantar pressure analysis in relatively long-distance walking for objective outcome evaluation of ankle osteoarthritis treatments, i.e., ankle arthrodesis and total ankle replacement.

METHODS

Forty-seven subjects in four groups: three patient groups and controls, participated in the study. Each subject walked twice in 50-m trials. Plantar pressure under the pathological foot was measured using pressure insoles. Six parameters: initial contact time, terminal contact time, maximum force time, peak pressure time, maximum force and peak pressure were calculated and averaged over trials in ten regions of foot. The parameters in each region were compared between patient groups and controls and their effect size was estimated. Besides, the correlations between pressure parameters and clinical scales were calculated.

FINDINGS

We observed based on temporal parameters that patients postpone the heel-off event, when high force in forefoot and high ankle moment happens. Also based on maximum force and peak pressure, the patients apply smoothened maximum forces on the affected foot. In ten regions, some parameters showed improvements after total ankle replacement, some showed alteration of foot function after ankle arthrodesis and some others showed still abnormality after both surgical treatments. These parameters showed also significant correlation with clinical scales in at least two regions of foot.

INTERPRETATION

Plantar pressure parameters in relatively long-distance trials showed to be strong tools for outcome evaluation of ankle osteoarthritis treatments.

Avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal: report of a case

Isolated avulsion fracture of the peroneus longus tendon insertion at the base of the first metatarsal is very rare. Similar to most avulsion fractures that result from excessive strain at a tendon or ligament insertion, this type of injury is caused by the strong tension exerted by the peroneus longus tendon. The mechanisms leading to this lesion and treatment options are not clearly defined. We present the case of an isolated minimally displaced intra-articular avulsion fracture at the plantar lateral base of the first metatarsal. Faced with a painful non-union following conservative treatment we considered excision of the bony fragment and first tarsometatarsal arthrodesis. This leads to a favourable functional outcome.

Ambulatory assessment of 3D ground reaction force using plantar pressure distribution

This study aimed to use the plantar pressure insole for estimating the three-dimensional ground reaction force (GRF) as well as the frictional torque (T(F)) during walking. Eleven subjects, six healthy and five patients with ankle disease participated in the study while wearing pressure insoles during several walking trials on a force-plate. The plantar pressure distribution was analyzed and 10 principal components of 24 regional pressure values with the stance time percentage (STP) were considered for GRF and T(F) estimation. Both linear and non-linear approximators were used for estimating the GRF and T(F) based on two learning strategies using intra-subject and inter-subjects data. The RMS error and the correlation coefficient between the approximators and the actual patterns obtained from force-plate were calculated. Our results showed better performance for non-linear approximation especially when the STP was considered as input. The least errors were observed for vertical force (4%) and anterior-posterior force (7.3%), while the medial-lateral force (11.3%) and frictional torque (14.7%) had higher errors. The result obtained for the patients showed higher error; nevertheless, when the data of the same patient were used for learning, the results were improved and in general slight differences with healthy subjects were observed. In conclusion, this study showed that ambulatory pressure insole with data normalization, an optimal choice of inputs and a well-trained nonlinear mapping function can estimate efficiently the three-dimensional ground reaction force and frictional torque in consecutive gait cycle without requiring a force-plate.

[Ankle arthroplasty. Rationale for interfaculty collaboration]

Arthroplasty has become increasingly popular as a solution for end-stage ankle arthrosis. Good results, with a 90% survival rate at ten years, have been reported with use of recent prostheses. However, the role of ankle arthroplasty needs to be more clearly defined. Due to its particular nature and specific biomechanical aspects, the ankle joint presents a real challenge for arthroplasty. Patient selection and surgical technique need to be optimized to improve long-term results. Careful clinical and biomechanical studies need to be conducted to objectively determine the long term benefit in terms of quality of life. To better address these points the authors of this manuscript have coordinated their expertise in a collaborative approach, so as to optimize surgical indications, prosthesis implantation, postoperative rehabilitation and research.

Post-traumatic overload or acute syndrome of the os trigonum: a possible cause of posterior ankle impingement

The purpose of this paper is to discuss the post-traumatic overload syndrome of the os trigonum as a possible cause of posterior ankle impingement and hindfoot pain. We have reviewed 19 athletes who were referred to our foot unit between 1995 and 2001 because of posterior ankle pain, and in whom a post-traumatic overload syndrome of os trigonum was diagnosed. All these patients were followed up over a period of 2 years. In 11 cases a chronic repetitive movements in forced plantar flexion was found. In the other eight cases the pain appeared to persist after a standard treatment of an ankle sprain in inversion plantar flexion. The diagnosis was based on clinical history, physical examination and X-rays that revealed a non-fused os trigonum. The confirmation of diagnosis was carried-out injecting local anaesthetic under fluoroscopic control. In all cases a corticosteroid injection as first line treatment was performed. In 6 cases a second injection was necessary to alleviate pain because incomplete recovery with the first injection. Three cases (16%) were recalcitrant to this treatment and in these three cases a surgical excision of the os trigonum was carried out. Our conclusion is that after some chronic athletic activity or an acute ankle sprain the os trigonum, if present, may undergo mechanical overload, remain undisrupted and become painful. Treatment by corticosteroid injection often resolves the problem.

The scarf osteotomy for the treatment of hallux valgus deformity: a review of 84 cases

This study reviewed the subjective, clinical and radiological outcome of 71 patients (84 feet) treated by scarf osteotomy for hallux valgus deformity at our institution from 1995 to 1998 with an average follow-up time of 22 months (range, 17 to 48 months). At the time of follow-up, 39% of the patients were very satisfied, 50% were satisfied and 11% were not satisfied. The mean AOFAS score raised significantly from 43 points (14-68) preoperatively to 82 points (39 to 100) at follow-up (p < 0.001). The radiological angles including M1-M2, M1-P1, M1-M5 and DMAA improved significantly (p < 0.001). Among the 16 complications recorded, seven (8%) were minor and nine (11%) required an additional procedure. The scarf osteotomy of the first metatarsal coupled with a lateral soft-tissue release and, in three-quarters of our cases, with a basal closing wedge varisation osteotomy of the first phalanx, resulted in overall high satisfaction rate as well as significant clinical and radiological improvements in our series. Nevertheless, the range of motion of the first MP joint remained low: 30 degrees to 74 degrees in 52 patients (62%) and <30 degrees in four patients (5%). Furthermore, the mobility of the first ray as well as the consequences of the procedure in the sagittal plane need to be assessed more accurately, and this may be achieved by incorporating measurement of the plantar pressures in the forefoot area into the global rating system.

Arthroscopic partial meniscectomy in patients over 70 years of age

PURPOSE

This study was conducted to determine the importance of age as a limiting factor as well as to assess the role of age in combination with cartilage damage or osteoarthritis as predicting factors for the outcome after arthroscopic partial meniscectomy.

TYPE OF STUDY

Case series.

METHODS

We reviewed 97 patients over 70 years of age who underwent an arthroscopic partial meniscectomy between 1992 and 1996. At the time of evaluation, 5 patients had died and 1 patient was unavailable, leaving 91 patients (95 knees) suitable for assessment. There were 56 women and 35 men. The average age at time of surgery was 74 years (range, 70 to 84 years). The mean follow-up period was 4 years (range, 2 to 6 years). Assessment of the cases by 1 investigator included medical records and preoperative radiographs of the knee joint, with the main interest focused on evidence of osteoarthritis using the classification of Kellgren and Lawrence. Evaluation of cartilage damage was performed on surgical videotapes according to Outerbridge. All 91 patients were personally interviewed by telephone. The questionnaire included influence of the operation on knee pain, quality and duration of satisfaction, requirement of further surgery, and whether the patient would undergo the same operation again.

RESULTS

According to the Kellgren and Lawrence classification, 80% of patients had radiographic evidence of osteoarthritis grade 0-2, and 20% had grade 3-4. According to Outerbridge, 43% of the patients had cartilage damage grade 0-2 and 57% had grade 3-4; 81% of the patients with osteoarthritis grade 0-2 and 83% of the patients with cartilage damage grade 0-2 had a satisfactory outcome when followed-up for more than 2 years. Among the patients with osteoarthritis grade 3-4 or cartilage damage grade 3-4, 55% and 69%, respectively, were satisfied when followed-up for more than 2 years; 45% and 37%, respectively, required a further surgery after 1 to 4 years. The grade of osteoarthritis had significant influence on satisfaction (P <.01), on whether the patients would have the operation done again (P =.01), and on whether they required further surgery (P =.04). The severity of cartilage damage only had a significant influence on whether the patients would undergo the operation again (P =.01).

CONCLUSIONS

Pre-existing degenerative changes appeared to affect the outcome more than the patient's age. However, arthroscopic partial meniscectomy was followed by satisfactory results in more than two thirds of our cases even if performed in the presence of moderate degenerative changes. But two thirds does not correspond with the good results usually obtained in a younger population. Therefore, the indication for surgery and the expected outcome have to be evaluated carefully in elderly patients.

Unusual localisation of tophaceous gout. A report of four cases and review of the literature

We report four cases with very unusual manifestations of tophaceous gout. All patients were male, aged between 29 and 67 years. Only one patient had an acute gouty arthritis in his medical history, whereas the other three had never developed clinical symptoms from their hyperuricemia. Two patients had gout tophi in the patella, while the others showed gout tophi in the space of bipartite bones, one in a bipartite patella and one in a tripartite sesamoid bone of the first toe. To our knowledge, gout tophi in the space of bi- or tripartite bones has never been described before.