胸腰椎骨折复位固定器的研制与临床应用

目的：探索一种简便有效的外固定器具来治疗胸腰椎骨折。方法：从生物力学角度，利用脊柱过伸复位，三点固定的原理，研制出一种复位固定器。该复位固定器的后板弧度可以调节，患者仰卧于弓起的后板上，通过患者自身的重量，达到缓慢过伸复位。复位后收紧固定带，使胸片的上、下端与后板的距离相对固定，防止再移位。结果：固定器法与二桌法相比，该法患者疼痛轻，不易疲劳，与石膏背心固定相比，该复位固定器轻巧，易被患者接受。适用于稳定型和轻度不稳定型胸腰椎骨折、无条件手术的严重不稳定型胸腰椎骨折，各种胸腰椎疾病手术后需要外固定的病人。结论：固定器法操作简单，效果确切，优于二桌法，是非手术治疗的良好补充。     

The Effect of Medial Release of the Distal Patellar Tendon Insertion on Lateral Patella Translation and Residual Insertion Strength: A Cadaveric Study

Patellar tendon avulsion is a risk with difficult exposure in a stiff knee, patella baja or previous tibial osteotomy. We sought to define a safe amount of release of the patellar tendon insertion for such cases. Eleven pairs of fresh frozen cadaveric lower limb specimens were acquired and randomized to either intact or partial release of the distal tibial insertion. Partial release of the tibial insertion of the tendon increased lateral exposure a mean 29% ± 15% (P = 0.002) while reducing ultimate strength to a mean of 80% that of the intact contralateral tendon. Measured patella release increased lateral patella translation and can be performed without risk of catastrophic rupture with basic activities of daily living following TKA.     

Intraoperative Fracture During Staged Total Knee Reimplantation in the Treatment of Periprosthetic Infection

Bone stock during knee reimplantation for infection is compromised and may contribute to intraoperative fracture. This study aims to describe the prevalence of said fractures. A retrospective review was performed of patients who underwent a staged TKA reimplantation for a periprosthetic infection. Patients who sustained an intraoperative fracture were analyzed. The fracture timing, location, and treatment were recorded. Fracture healing, component stability, and need for re-revision were noted. Between 1990 and 2010, 894 reimplantations were performed. Twenty-three fractures occurred in 21 patients (2.3%) with mean follow-up of 56 months (range: 4–122). Thirteen fractures occurred in femora, 7 in tibiae, and 3 in patellae. Four occurred during resection, while 19 occurred during reimplantation. Observation and wires/cables were the most common treatments utilized. At final follow-up, 91% of fractures demonstrated union and 75% of patients demonstrated stable components. Eight patients (38%) required a revision, the majority of which were performed for re-infection.     

The Impact of Patellar Resurfacing in Two-Stage Revision of the Infected Total Knee Arthroplasty

Evidence for optimal management of the patellofemoral joint in revision surgery for the infected TKA is limited. We reviewed 69 infected TKAs undergoing two-stage revision. Fifty four patellae were resurfaced, 11 had patelloplasty performed, two were augmented with trabecular metal, one had impaction grafting, and one knee underwent patellectomy. Average follow-up was 4.5 years. The patients that received patellar resurfacing at re-implantation experienced statistically significant improvements in KSS pain score, functional KSS, and patellar score (P < 0.03). One further patient treated with impaction grafting improved significantly in terms of pain and function. Patients treated with patelloplasty, trabecular metal augmentation, or patellectomy did not have significant improvements in clinical or functional outcome. Patient age, use of dynamic vs. static spacer, use of extensor mechanism release, and differences in Charlson index did not seem to statistically affect outcome. We recommend that every effort should be made to minimize patellar bone loss in first stage resection, as inability to resurface the patella at time of reimplantation may adversely affect patient outcome.     

Segmental neck of femur fractures: A unique case report of an ipsilateral subcapital,greater trochanteric and intertrochanteric fracture and proposed management algorithm

INTRODUCTION

Neck of femur fractures are now increasingly common in an ageing population. The management is well known and has been described in great detail. Concomitant ipsilateral segmental fractures of the neck of femur (SFNOF) however are rare and their investigation and management is poorly described.

PRESENTATION OF CASE

We present the surgical management of a unique and complex case of an ipsilateral subcapital, greater trochanteric and intertrochanteric fracture sustained in an 87-year-old female following a low trauma injury. This fracture configuration has not been described in the literature to date, neither has our method of reconstruction for this fracture, namely hemiarthorplasty, trochanteric stabilising plate and cerclage wires.

DISCUSSION

15 cases from 1989 to 2011 managed by 8 different fixation devices and followed up for an average of 17 months (2–58 months). There was an initial mortality rate of 13% (n = 2). All associated with low energy trauma occurred in female (n = 8), and most with high energy trauma occurred in males (83%; n = 5). The diagnosis was delayed or missed in 20% of cases, and the most common pattern was a concomitant undisplaced subcapital and intertrochanteric fracture (37.5%, n = 6). The overall risk of avascular necrosis was 20%, with a greater risk in patients greater than 65 years of age (33%).

CONCLUSION

Ipsilateral SFNOF are rare injuries with a bimodal distribution, and carry a greater risk of AVN. We advise that all SFNOF should have pre-operative CT planning and propose an algorithm to treat these patients with a standardised surgical approach.     

Imaging and histopathological evaluation of a cystlike formation in subchondral insufficiency fracture of the femoral head: A case report and literature review

INTRODUCTION

In the majority of subchondral insufficiency fractures (SIFs) of the femoral head, T₁-weighted magnetic resonance imaging shows an irregular, serpiginous, low-intensity band that is convex to the articular surface. We report a case of a cystlike formation in SIF of the femoral head in an elderly woman.

PRESENTATION OF CASE

A 71-year-old woman reported right hip pain without any history of antecedent trauma. The initial radiograph showed a slight narrowing of the joint space in the right hip. The patient was treated with conservative therapy for 2 months. Radiographs obtained 3 months after the onset of pain showed non-progressive joint-space narrowing. T₁-weighted magnetic resonance images obtained 2 months after pain onset revealed a round, cystlike, low-intensity area just beneath the articular cartilage. The patient underwent total hip arthroplasty. Histopathological examination showed fracture callus and granulation tissue in the subchondral area, surrounded by vascular-rich granulation tissue and fibrous tissue, which corresponded to the round, low-intensity band observed on the T₁-weighted image.

DISCUSSION

This case was a rare SIF of the femoral head which had a cystlike formation with a low signal intensity on T₁-weighted images and a very high signal intensity on STIR sequences in the superolateral portion of the femoral head, surrounded by a pattern of edema in the bone marrow. To our knowledge, no similar cases were cited in the literature.

CONCLUSION

It is important for surgeons to keep in mind that sometimes SIFs of the femoral head can appear as a round cystlike formation.