Factors related to the early outcome of medial open wedge high tibial osteotomy: coronal limb alignment affects more than cartilage degeneration state.

INTRODUCTION: This study aimed to identify possible factors influencing the early outcome after medial open wedge high tibial osteotomy (MOWHTO). MATERIALS AND METHODS: A total of 87 MOWHTO cases with a minimum of 2-year follow-up and second-look arthroscopic results available were enrolled. The cartilage degeneration state was evaluated by the International Cartilage Repair Society (ICRS) grading. Radiographic parameters including the hip-knee-ankle axis (HKA), medial proximal tibia angle (MPTA), posterior tibial slope, patellar height, mechanical lateral distal femoral angle (LDFA), joint line convergence angle (JLCA), joint line obliquity (JLO), and weight-bearing line ratio (WBLR) were measured. The pre-operative arthritic change was evaluated by Kellgren-Lawrence (KL) classification. According to the post-operative HKA, knees were divided into three (Under/Optimal/Over-correction) subgroups. Subjective International Knee Documentation Committee (IKDC) scores were evaluated and factors related to post-operative IKDC scores were analyzed. RESULTS: The pre-operative HKA (P = 0.002), post-operative HKA (P = 0.007), pre-operative MPTA (P = 0.011), and pre-operative WBLR (P = 0.031) were significantly related to the post-operative IKDC score. Cartilage degeneration states evaluated from first and second-look arthroscopy were not associated with post-operative IKDC score. Subgroup analysis revealed that the Under-correction group had significantly lower post-operative IKDC scores compared to the Optimal and Over-correction group (P = 0.012 and P = 0.030, respectively). CONCLUSION: Our result suggests that a sub-optimal correction of coronal limb alignment negatively affects the early outcome of MOWHTO. On the other hand, the effect of the degree of cartilage degeneration was not significant.

Early Return to Daily Life through Immediate Weight-Bearing after Lateral Malleolar Fracture Surgery.

Lateral malleolus fracture is one of the most common fractures. However, there is controversy regarding the rehabilitation protocols used after surgery. In particular, the initiation point for weight-bearing has not been standardized. In the present study, we investigated the prognostic difference between immediate and delayed weight-bearing on lateral malleolus fractures. The medical records of matched patients in the immediate and delayed weight-bearing groups (50 and 50, respectively) were reviewed retrospectively. All patients were treated with open reduction and internal fixation using an anatomical locking compression plate with a lag screw. In the immediate weight-bearing group (IWB), tolerable weight-bearing (i.e., what can be endured immediately after surgery with crutches) was permitted. In the delayed weight-bearing group (DWB), weight-bearing was completely restricted for 4 weeks after surgery. Ankle motion exercise was permitted in both groups, starting from the day after surgery. Radiographic assessment data and clinical outcomes were reviewed between the two groups. No significant differences in radiographic assessments and complications were found between the two groups. Significant differences in terms of a shortened length of hospital stay and time to return to work with the IWB rehabilitation protocol compared with DWB were confirmed (6.0 vs. 9.2 days, p = 0.02 and 6.1 vs. 8.3 weeks, p = 0.02, respectively). A significant difference in sport factor was observed in the Foot and Ankle Outcome Score at 3 months postoperatively (72.3 vs. 67.4, p = 0.02). We found no significant differences between the two groups concerning postoperative radiological outcomes and complications. The benefits of shortening the time to return to work and length of hospital stay associated with the IWB rehabilitation protocol were confirmed. In conclusion, immediate weight-bearing is recommended in patients with lateral malleolus fracture after anatomical reduction and firm fixation by surgery.

Incidence and Factors Affecting the Occurrence of Lateral Hinge Fracture After Medial Opening-Wedge High Tibial Osteotomy.

BACKGROUND: Few clinical studies have reported the predictors of lateral hinge fracture (LHF) after medial opening-wedge high tibial osteotomy (MOWHTO). PURPOSE/HYPOTHESIS: The purpose was to compare the incidence of LHF on plain radiographs versus computed tomography (CT) scans and to investigate the factors related to the development of LHF after MOWHTO. We hypothesized that (1) a higher LHF detection rate would be seen on CT scans versus plain radiographs and (2) LHF incidence would be related to opening gap width and hinge position. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: A total of 97 MOWHTO cases were included. The presence and types of LHF were determined from plain radiographs and CT scans. Radiographic parameters were measured on plain radiographs taken 6 weeks postoperatively. Anterior and posterior opening gap widths, coronal and sagittal osteotomy slopes, and fibular height were calculated from CT scans. The wedge-hinge relationship and the zone of hinge position were assessed, and the patient and radiographic factors related to LHF occurrence were evaluated. RESULTS: Seventeen LHF cases (20.5%) were detected on plain radiographs, while significantly more (37 cases; 44.6%) were found on CT scans (P = .001). Based on Takeuchi classification, 28 LHF cases were considered type 1, 7 were type 2, and 2 were type 3. Logistic regression analysis revealed that opening gap width (odds ratio, 1.615; 95% confidence interval, 1.232-2.118; P = .001) and posterior opening gap width (odds ratio, 3.731; 95% confidence interval, 1.642-4.351; P = .008,) differed significantly between patients with versus without LHF. Other patient and radiographic factors were not significantly related to LHF occurrence. Receiver operating characteristic curve analysis identified the opening gap width cutoff values for LHF as 11.0 mm (area under the curve, 0.81; sensitivity, 78.4%; specificity, 73.9%). CONCLUSION: The incidence of LHF after MOWHTO can be underestimated on plain radiographs compared with CT scans. Only large opening gap width, especially posterior gap width, was found to have a statistically significant relationship with occurrence of LHF. Therefore, special caution for possible LHF may be needed if a large correction is planned.

Magnetic Resonance Imaging of Patellofemoral Morphometry Reveals Age and Gender Variations in the Knees of Children and Adolescents.

BACKGROUND: The morphology and alignment of the patellofemoral joint are crucial risk factors for patellar instability, and the incidence of acute primary patellar dislocation is the highest in women in their second decade of life. The purpose of the study was to analyze age and gender variations of the patellofemoral joint using magnetic resonance imaging (MRI). METHODS: A total of 852 patients aged between 4 and 18 years with a history of knee MRI examinations were screened for eligibility and 663 patients (470 males, 193 females) were included. Patients were divided into groups according to age and sex. The age group was divided into five groups (Group 1, 4-6 years; Group 2, 7-9 years; Group 3, 10-12 years; Group 4, 13-15 years; and Group 5, 16-18 years). Three orthopaedic surgeons measured MRI parameters reflecting the patellofemoral morphology (sulcus angle, lateral trochlear inclination, trochlear facet symmetry, and femoral depth) and alignment (tibial tuberosity-trochlear groove distance, percent sulcus location, and percent tibia tuberosity location). RESULTS: Parameters including tibial tuberosity-trochlear groove distance, sulcus angle, percent tibial tuberosity location, trochlear facet symmetry, and femoral depth showed significant differences between the age groups (p < 0.05). The sulcus angle decreased fin Group 2, and the femoral depth showed an increasing trend with aging in male patients. However, the sulcus angle in females decreased first and then increased in Group 3 as the inflection point. The femoral depth showed an opposite pattern. CONCLUSIONS: Patellofemoral morphometry showed age and gender variation. Notably, the sulcus angle and femoral depth were significantly different between males and females and changed according to the development. These findings may reflect the sex difference and peak incidence of the patellar instability risk. Understanding the morphological changes and differences of the patellofemoral joint may facilitate the diagnosis of patellofemoral pathologies.

Effect of metatarsal osteotomy and open lateral soft tissue procedure on sesamoid position: radiological assessment.

BACKGROUND: Incomplete sesamoid reduction is a potential risk factor for the recurrence of hallux valgus. The purpose of this study was to radiologically investigate changes in sesamoid position after chevron osteotomy and the open lateral soft tissue procedure. METHODS: Sixty-eight feet that underwent operative correction for hallux valgus deformity were reviewed consecutively. The hallux valgus angle (HVA), first to second intermetatarsal angle (IMA), tibial sesamoid position (TSP), distance of the fibular sesamoid (DFS), and translation of the metatarsal head (TMH) were evaluated preoperatively and at final follow-up. RESULTS: While most parameters were significantly decreased after surgery, no significant change in DFS (correction - 1.45 mm, p = 0.08) was noted. The difference between preoperative and postoperative TSP values (ΔTSP) has a moderately positive correlation with difference in TMH values (ΔTMH) (Rho 0.475, p = .000). Other parameters were similarly correlated. CONCLUSIONS: First, metatarsal bone realignment reduced the sesamoid, but its position, relative to the second metatarsal axis (DFS), was unchanged. The sesamoid is reduced by the lateral translation of the first metatarsal but not by medial sesamoid migration.

Primary exploration for radial nerve palsy associated with unstable closed humeral shaft fracture.

BACKGROUND: The treatment of radial nerve palsy caused by closed humeral shaft fracture is a matter of debate. The purpose of this study is to evaluate the outcome of early surgical management of radial nerve palsy in patients with unstable closed humeral shaft fractures and to determine whether patients with this injury should be surgically explored. METHODS: Medical records of 15 consecutive patients who had undergone open reduction and internal fixation for unstable closed humeral shaft fractures were reviewed. Injury mechanisms, radiographs, intraoperative findings of the injured nerve, and clinical improvement were analyzed. Of the 15 patients, two were injured during simple falls, two during baseball pitching, one by a fall from a height, one during skiing, and one by direct machine impaction during work. Fracture locations were middle humerus in six patients, middle-distal in eight patients, and middle-proximal in one patient. Fracture patterns were transverse fracture in six patients, butterfly segment fracture in four patients, oblique segment fracture in three patients, and spiral fracture in two patients. RESULTS: Eleven patients showed macroscopically intact nerves, and four had total nerve transection. All four patients with total nerve transection were injured in traffic accident. Of these four patients, one showed comminuted fracture with butterfly fragment on the middle-distal shaft and the other three showed displaced transverse fracture on the middle to middle-distal shaft area. Transected nerves were directly repaired in two patients. In the other two patients, humerus shortening and nerve grafting were performed because of mangled nerve endings. All patients who had intact nerves showed fully recovered function at the last follow-up. CONCLUSION: For radial nerve palsy accompanied by unstable humeral shaft fracture, primary exploration of the radial nerve and open reduction and plate fixation of the fracture should be considered as a treatment of choice. High-energy trauma, fracture location at the middle-distal humerus, and simple transverse fracture or comminuted fracture with butterfly fragment seems to be risk factors for radial nerve transection.