Changes in the femoral osteotomy level coefficient and neck shaft angle during limb lengthening with an intramedullary magnetic nail.

BACKGROUND: The intramedullary magnetic IM nail enables bone graduated distraction. Proximal femur osteotomies for ante grade IM lengthening nails have a tendency towards varus-procurvatum malalignment. We examined the effect of the level of the osteotomy and of trochanteric versus piriformis entry points on the neck shaft angle (NSA) during lengthening with the PRECICE IM magnetic nail. METHODS: A novel parameter, the osteotomy level coefficient (OLC), was introduced as a guide to determine the level of an osteotomy at the proximal femur. The OLC was defined as the ratio between the distances from the tip of the greater trochanter to the osteotomy divided by the full length of the femur. A retrospective review of all femoral lengthening procedures with the PRECICE ante grade IM lengthening nail between 2013 and 2018 was carried out. RESULTS: 31 femurs were lengthened in 30 patients (16 males and 14 females, mean age at surgery years 17.1. The average amount of lengthening was 4.4 cm. Trochanteric entry points were used in 24 femurs, and piriformis entry points in seven femurs. The OLC values ranged from 0.16 to 0.34 (average 0.25). The average follow-up period was 10.15 months. The distraction index average 10.5 days/cm (Range 8.6-11.9), Consolidation index 32.1 days/cm (14.3-51.9). The average post-operative NSA was significantly reduced from 133.5º to 128.5º [t (31) = 5.57, p = 0.000]. There was no correlation between the OLC and the change in the NSAs. The trochanteric entry point showed a greater tendency to reduce the NSA (Mdif = - 6, SD = 4.8) compared to the piriformis entry point (Mdif = - 0.86, SD = 2.27) [t (31) = -3.96, p = 0.001]. CONCLUSION: Proximal femur lengthening with the PRECICE IM nail significantly reduced the NSA and might cause Varus deformity. The level of osteotomy by OLC did not influence the amount of NSA reduction. The trochanteric entry points have a greater tendency to reduce the NSA compared to the piriformis entry points.

Four-in-one Extensor Realignment for the Treatment of Obligatory or Fixed, Lateral Patellar Instability in Skeletally Immature Knee.

BACKGROUND: Congenital (fixed) and obligatory (habitual) patellar dislocations in children are a complex clinical and surgical challenge. Numerous individual surgical techniques have been described. This study aims to assess results, patient satisfaction, and complications after a combined Roux-Goldthwait procedure, vastus medialis obliquus advancement, Galeazzi procedure, and extensive, lateral release (4-in-1 extensor realignment) in the skeletally immature knee with obligatory, or fixed lateral patellar instability. METHODS: Records of children with congenital fixed or obligatory patellar instability, who underwent the 4-in-1 procedure at a single institution, were reviewed. Clinical results included ability and time for the return to activities of daily living (ADL) and sport, recurrent instability and/or dislocation, and necessity of long-term bracing. Continued pain was assessed by the Kujala Score. Complications including infection, recurrent instability, and the necessity for secondary procedures were recorded. RESULTS: A total of 34 patients (46 knees) mean age 10.3±2.4 years, underwent the 4-in-1 procedure with a mean postoperative follow-up of 51.6±31.5 (range, 12 to 146) months. Sixteen patients (22 knees) responded to a phone interview and questionnaire. All 16 patients returned to ADL in a mean time of 10.3±2.4 weeks. Ninety-one percent returned to sport in a mean time of 23.1±15.5 weeks. Long-term bracing was required for 6 knees after the surgery. The mean Kujala Score was 93.0±5.2 (range, 83 to 100). Complications included 6 of 34 patients (18%) with recurrent instability at the latest follow-up and 2 with superficial wound infection. CONCLUSIONS: Patients with obligatory or fixed lateral, patellar instability who undergo the 4-in-1 procedure have good short-term results with low complication rates. Return to ADL and sporting activity with minimal pain can be expected, usually without the need for long-term bracing. The 4-in-1 procedure is a viable option for skeletally immature patients with obligatory or fixed, lateral patellar instability. LEVEL OF EVIDENCE: Level IV-Therapeutic study.

[Hip arthroscopy: differential diagnosis of pain around the hip joint].

Hip arthroscopy is one of the most highly evolving surgical techniques in recent years. It plays a major role in the diagnosis and treatment of a broad spectrum of hip pathologies. The evaluation of the painful hip requires meticulous history taking, elaborated physical examination, and basic and advanced imaging modalities. The differential diagnosis includes a continuously growing number of diagnoses. Once considered an "operation looking for indications", the current indications for hip arthroscopy are based on a better understanding of pathologies around the hip joint. The results of recently published intermediate and long term clinical outcome studies are encouraging. Ongoing, comprehensive understanding of the correlation between pathologies and clinical presentation will improve the surgical technique, which in turn may become a joint preserving operation.

Probability analysis of sequential SCFE (PASS score).

PURPOSE: The study aimed to develop a scoring system based on clinical and radiological findings to predict the risk of a sequential slipped capital femoral epiphysis (SCFE). METHODS: Paediatric patients with unilateral SCFE and at least two years of radiographic follow-up were screened for inclusion. Medical records were reviewed for multiple variables including age, gender, body mass index (BMI), stability of SCFE, and time to sequential presentation. Radiographic analysis included triradiate physeal status, Risser staging, superior epiphyseal extension ratio (EER), posterior epiphyseal angle (PEA), posterior sloping angle (PSA) and slip severity. RESULTS: In total, 163 patients (88 male, 54%, 75 female, 46%) met inclusion criteria. Of those, 65 (40%) with a mean age of 11.9 ± 1.3 years developed sequential SCFE at a mean of 9.8 ± 6.4 months after the initial slip. Eight independent variables were statistically different (p < 0.05) between unilateral and sequential groups. Following multivariate analysis, Risser stage and triradiate status were no longer significant and did not influence the strength of the final model (overall area under the curve (AUC) = 0.954) and were consequently excluded. We developed the PASS score using three radiographic parameters using chosen cut-off values that were close to their maximized value and weighted the point value assigned to each parameter based on the strength of predictor. CONCLUSION: A PASS score of three or higher predicts a high probability of sequential SCFE with 95% confidence and may warrant prophylactic screw fixation. PASS score calculation can be used to predict a sequential SCFE and provide an objective method to determine the utility prophylactic screw fixation. LEVEL OF EVIDENCE: II.