Transulnar styloid palmar scapho-lunate dislocation with median nerve injury

A patient with a transulnar styloid palmar scapho-lunate dislocation with median nerve injury is described. The dislocation could be reduced by closed manipulation under anaesthesia, and the scapho-lunate ligament was repaired subsequently using a Mytek Micro bone anchor. This case is reported for its rarity and its management. Although closed reduction can be achieved by manipulation, scapho-lunate ligament repair is essential to prevent rotatory instability of the scaphoid with this pattern of injury.     

Greater Arch Injuries

Dislocations and fracture dislocations of carpal bones are uncommon injuries which invariably poses challenges in the management. Perilunate fracture dislocations are the combination of ligamentous and osseous injury that involve the “greater arc” of the perilunate associated instability. Despite their severity, these injuries often go unrecognized in the emergency department leading to delayed diagnosis and treatment. A Prospective study was done from June 2008 to December 2013 in 15 cases of complex wrist injuries which included of greater arch injuries, perilunate fracture dislocation and one dorsal dislocation of Scaphoid. 10 cases of perilunate fracture dislocation underwent open reduction and internal fixation with Herbert screw and k-wire, 4 cases of greater arch injury underwent closed reduction and kwire fixation and one case of neglected dorsal dislocation underwent proximal row carpectomy. One patient had Sudecks osteodystrophy 1 had Scaphoid nonunion and 6 had median nerve compression. Overall outcome according to Mayo wrist score was 53 % excellent, 33 % good and 14 % fair. Greater arch injuries are difficult to treat because injuries to many ligaments are involved and failure to recognize early leads to persistent pain, disability and early onset of arthritis. Prompt recognition requires CT scan and MRI. Management requires reduction and multiple K-Wiring according to merits of the case.     

Modeling Dislocations at Different Scales

In this article, we give an introduction to the basic theory of dislocations and some dislocation models at different length scales. Dislocations are line defects in crystals. The continuum theory of dislocations works well at the length scale of several lattice constants away from the dislocations. In the region surrounding the dislocations (core region), the crystal lattice is heavily distorted, and atomistic models are used to describe the atomic arrangement and related properties. The Peierls-Nabarro models of dislocations incorporate the atomic features into the continuum theory, therefore provide an alternative way to understand the dislocation core properties. The numerical simulation of the collective motion and interactions of dislocations, known as dislocation dynamics, is becoming a more and more important tool for the investigation of the plastic behaviors of materials. Several simulation methods for dislocation dynamics are also reviewed in this article.     

急性下颈椎交锁型和水平脱位并脊髓损伤

目的探讨急性颈椎交锁和水平脱位并脊髓损伤的治疗方法。方法采用徒手复位和牵引相结合的方法治疗急性下颈椎交锁脱位、水平脱位伴骨折,并有不同程度脊髓和神经根受压损伤１５例病人。结果本组治疗１３例得到６～１８月的随访,平均１１月。有１２例脊柱稳定,无继发性滑脱,无显性脊柱退变和迟发脊髓损伤。脊髓和神经根恢复分优者４例、良者６例、可者２例、差者１例;优良率达８０％。结论急性下颈椎交锁及水平脱位,临床可以通过徒手复位和牵引相结合的方法,达到理想复位。结合脱水剂、微血管扩张剂、糖皮质激素和神经介质等药物应用,促进脊髓神经组织恢复。     

Epidemiology of Bearing Dislocations After Mobile-Bearing Unicompartmental Knee Arthroplasty: Multicenter Analysis of 67 Bearing Dislocations

BackgroundThis study investigated the epidemiology and causes of bearing dislocations following mobile-bearing unicompartmental knee arthroplasty (MUKA) and determined whether the incidence of primary bearing dislocations decreases as surgeon experience increases.MethodsWe retrospectively reviewed the bearing dislocations following MUKAs performed by 14 surgeons with variable experience levels. Causes of bearing dislocations were determined based on the surgical records, radiographs, and operator’s suggestion. Using a chi-squared test, the incidence of bearing dislocation was compared between the first 50, the second 50, and the next 100 unicompartmental knee arthroplasties (UKAs) of each surgeon's cohort.ResultsThere were 67 (3.6%) bearing dislocations from 1853 MUKAs. The mean time to bearing dislocations after index MUKAs was 33 months (range, 1-144 months); 55% of the bearing dislocations occurred within 2 years after the index MUKAs. Primary bearing dislocations (n = 58) were the most common, followed by secondary (n = 6) and traumatic dislocations (n = 3). There was no significant difference in the incidence of bearing dislocation between the first 50 and second 50 UKAs for each surgeon. Two surgeons showed a significant decrease in bearing dislocations in their second 100 UKAs, while the other surgeons did not show a difference between their first 100 and second 100 UKAs.ConclusionMost bearing dislocations after MUKAs were related to technical errors such as component malposition or gap imbalance. This study did not confirm that the incidence of bearing dislocations decreases as the number of cases increases.Level of EvidenceIV, Case series.     

Isolated volar surgical approach for the treatment of perilunate and lunate dislocations

Background:

Volar and/or dorsal surgical approaches are used for surgical treatment of perilunate and lunate dislocations. There are no accepted approaches for treatment in the literature. We evaluated the functional results of isolated volar surgical approach for the treatment of perilunate and lunate dislocation injuries.

Materials and Methods:

9 patients (6 male and 3 female patients average age 34.5 ± 3.6 years) diagnosed with perilunate or lunate dislocations between January 2000 and January 2009 were involved in the study. The reduction was performed through isolated volar surgical approach and K-wire fixation, fracture stabilization with volar ligament repair was performed. Range of wrist joint motion, fracture healing, carpal stability, grip strength, return to work were evaluated and also direct radiographs were taken routinely at each control. The scapholunate interval and the scapholunate angle were evaluated radiographically. Evaluations of the clinical results were done using the DASH, VAS and Modified Mayo Wrist Scores.

Results:

The physical rehabilitation was started at 6^th week, after the K-wires were removed. The average followup was 18.2 months (range 12-28 months). At the final followup, the average flexion extension arc was 105.0 ± 9.6° (74.6% of the other side), the average rotation arc was 138.8 ± 7.8° (81.5% of the other side) and the average radioulnar arc was 56.1 ± 9.9° (86.4% of the other side). The grip strength was 0.55 bar; 83.2% that the uninjured arm. According to the Mayo Modified Wrist score, the functional result was excellent in five patients and good in four and the average DASH score was 22.8. The scapholunate interval was 2.1 mm and scapholunate angle was 51°.

Conclusion:

The clinical and radiological results of the isolated volar surgical approach were satisfactory. The dorsal approach was not needed for reduction of dislocations during operations. Our results showed that an isolated volar approach was adequate.     

踝关节骨折脱位手术治疗

目的探讨踝关节骨折脱位手术治疗。方法回顾性分析56例踝关节骨折脱位手术治疗。按照不同类型骨折脱位予不同的手术治疗方案。结果参照Weber评定结果,根据患者的手术恢复状况分为优、良、可、差;其中优27例,良19例,可6例,差4例;优良率达82%。结论在开放手术治疗踝关节骨折脱位过程中,重视外踝及后踝的复位和内固定,整复固定下胫腓联合分离及正确处理踝关节韧带是手术的重要环节。     

髋关节后脱位合并股骨头骨折的治疗探讨

目的 :通过治疗 19例髋关节后脱位合并股骨头骨折就其治疗方法、手术入路及并发症进行探讨。方法 :1985～ 1988年 ,共收治此类损伤 19例 ,将其分为 4型 ,Ⅰ型 3例 ,Ⅱ型 6例 ,Ⅲ型 1例 ,Ⅳ型 9例 ,根据各类分型的不同创伤病理改变 ,对其采用不同的治疗方法。结果 :经最短 1年 ,最长 14年随访 ,19例中 ,疗效优 12例 ,良 2例 ,可 3例 ,差 2例 ,优良率为 74%。结论 :治疗效果的关键是对此类病的正确认识和处理 ,髋关节后侧切口是手术治疗的主要手术途径。并发症的出现与创伤的严重程度有关。     

Traumatic Bilateral Knee Dislocations, Unilateral Hip Dislocation, and Contralateral Humeral Amputation: A Case Report

Bilateral traumatic knee dislocations are a rarity. We report a case of bilateral traumatic knee dislocations with concomitant right hip dislocation and complete traumatic amputation of the left, nondominant upper extremity at the level of the proximal one-third of the humerus. Angiograms revealed no evidence of popliteal artery injury. Orthopedic treatment consisted of immediate reduction of the dislocations and urgent revision amputation of the upper extremity. Staged, bilateral knee ligamentous reconstructions were performed on hospital days 24 and 29, respectively. Despite this constellation of devastating injuries, the patient had a satisfactory outcome. In patients with high-energy hip or knee dislocations, the bilateral hips and knees should be carefully examined to check for associated fractures and/or dislocations.