Do stand-alone interbody spacers with integrated screws provide adequate segmental stability for multilevel cervical arthrodesis?

Background contextSome postoperative complications after anterior cervical fusions have been attributed to anterior cervical plate (ACP) profiles and the necessary wide operative exposure for their insertion. Consequently, low-profile stand-alone interbody spacers with integrated screws (SIS) have been developed. Although SIS constructs have demonstrated similar biomechanical stability to the ACP in single-level fusions, their role as a stand-alone device in multilevel reconstructions has not been thoroughly evaluated.PurposeTo evaluate the acute segmental stability afforded by an SIS device compared with the traditional ACP in the setting of a multilevel cervical arthrodesis.Study designIn vitro human cadaveric biomechanical analysis.MethodsThirteen human cadaveric cervical spines (C2–T1) were nondestructively tested with a custom 6 df spine simulator under axial rotation, flexion-extension, and lateral bending loading. After intact analysis, eight single-levels (C4–C5/C6–C7) from four specimens were instrumented and tested with ACP and SIS. Nine specimens were tested with C5–C7 SIS, C5–C7 ACP, C4–C7 ACP, C4–C7 ACP+posterior fixation, C4–C7 SIS, and C4–C7 SIS+posterior fixation. Testing order was randomized with each additional level instrumented. Full range of motion (ROM) data were obtained and analyzed by each loading modality, using mean comparisons with repeated measures analysis of variance. Paired t tests were used for post hoc analysis with Sidak correction for multiple comparisons.ResultsNo significant difference in ROM was noted between the ACP and SIS for single-level fixation (p>.05). For multisegment reconstructions (two and three levels), the ACP proved superior to SIS and intact condition, with significantly lower ROM in all planes (p<.05). When either the three-level SIS or ACP constructs were supplemented with posterior lateral mass fixation, there was a greater than 80% reduction in ROM under all testing modalities (p<.05), with no significant difference between the ACP and SIS constructs (p>.05).ConclusionsThe SIS device may be a reasonable option as a stand-alone device for single-level fixation. However, SIS devices should be used with careful consideration in the setting of multilevel cervical fusion. However, when supplemented with posterior fixation, SIS devices are a sound biomechanical alternative to ACP for multilevel fusion constructs.     

锁定型后足融合髓内钉在踝关节融合术中的运用

目的 对锁定型后足融合髓内钉内固定结合自体骨移植术在踝关节融合术中的临床应用疗效进行评价。方法本科于2016年6月至2018年6月收治各类踝关节终末期疾病患者9例,使用踝关节前正中入路暴露踝关节及胫骨远端,截除踝关节各软骨面至软骨下松质骨外露,植入自体髂骨,使踝关节固定于中立位,足跟外翻5°,足外旋5°,使用进口锁定型后足融合髓内钉(SmithNephew)逆行穿钉固定。结果 所有患者随访12～24个月,行踝关节X线检查提示踝关节完全融合。使用AOFAS足踝功能评价系统,对手术前后行走功能、疼痛感、关节活动度等方面进行评价,AOFAS评分由术前(40.60±10.50)分增加至末次随访后(82.60±6.50)分,手术前后对比差异有统计学意义(t=23.25,P0.05)。本组优7例,良2例。结论 锁定型后足融合髓内钉内固定系统融合率高、固定坚强、操作规范简便,可运用于大部分踝关节终末期疾病患者的踝关节融合术。     

AO-wrist arthrodesis: with and without arthrodesis of the third carpometacarpal joint

The incorporation of the third carpometacarpal joint (CMCJ-3) during wrist arthrodesis is controversial. This retrospective study of 146 consecutive wrist arthrodeses with AO plate fixation specifically addresses this question. In 79 wrist arthrodeses the CMCJ-3 was also arthrodesed, and in 67 the CMCJ-3 was simply bridged. Problems relating specifically to the CMCJ-3 could not be analyzed clearly with the plate in situ. Therefore after plate removal only 81 wrists were evaluated with respect to the CMCJ-3. Of 47 wrists that had CMCJ-3 arthrodesis and plate removal, 20 developed a nonunion. Eleven of these were painful and further surgical treatment was required. In contrast, of 34 wrists with the CMCJ-3 bridged all but one remained free of symptoms after the plate had been removed. We conclude that the CMCJ-3 must not be included in the arthrodesis when performing an AO-wrist arthrodesis.     

First metatarsophalangeal joint arthrodesis: A new technique of internal fixation by using memory compression staples

A prospective clinical study of first metatarsophalangeal joint arthrodesis using memory compression staples is presented. In 27 patients, 30 feet underwent surgery. There were 24 women and 3 men, with a mean age of 61.2 years. Two memory compression staples were used at right angles to each other to achieve compression at the fusion site. Postoperatively, patients were allowed full weightbearing in a rigid-soled shoe. Subjective assessment was performed with a standard questionnaire, which included questions regarding level of pain, ambulation, and patient satisfaction. Objective assessment was performed by a clinical and included a radiographic examination. There was a postoperative reduction in the pain score from 4.6 to 1.6 (P < .0001). Ambulation ability improved from 4 to 2.5 (P < .0001). Patients reported 86.6% excellent to good results, and 96.7% achieved radiographic fusion at an average 8.2 weeks. The only significant postoperative complication was a single nonunion. The authors advocate memory compression staples for the internal fixation of first metatarsophalangeal joint arthrodesis. The implant is low profile, and postoperative cast immobilization is not required. The use of this device has a predictable success rate comparable to previously reported methods.     

Canine carpal joint fusion: a model for four-corner arthrodesis using a porous tantalum implant

PURPOSE: Interest has focused on porous materials that promote bony ingrowth. In this study a porous tantalum implant was used as an adjunct to intercarpal stabilization in a canine model of wrist arthrodesis. METHODS: A defect was created at the junction of the radiocarpal, ulnocarpal, and fourth carpal bones, analogous to a four-corner fusion site in humans. A tantalum cylinder was press-fit and stabilized with K-wires. Controls were represented by creating the defect without implant placement. Animals were killed at 4, 8, and 12 weeks. RESULTS: Histology showed bony ingrowth as early as 4 weeks and mechanical testing showed a statistically significant increase in strength of the construct over time. Controls failed to achieve union at any time point. CONCLUSIONS: The implant served as an adjunct to stabilization of the carpus in this model of four-corner fusion, suggesting a novel application of this material in conditions in which bone graft has been required previously. This study represents a preliminary investigation of the use of a tantalum device for intercarpal stabilization; it does not compare this technique with conventional methods.     

Anatomic basis for a minimally invasive approach to the subtalar joint

Introduction An isolated arthrodesis of the talocalcaneonavicular joint is a common indication in cases of pain and post-traumatic arthroses.Materials and methods Because of the high infection rate after surgery with the lateral incision, the authors decided to evaluate an alternative, minimally invasive procedure. Joint destruction was carried out via a posterolateral access after the insertion of two guidewires. For an evaluation of the risk for vessel and nerve structures, 102 ankle joint specimens preserved in formalin/alcohol were examined. Additionally, the minimally invasive access was evaluated in ten ankle joint specimens.Results Neither in the specimen nor during evaluation of the minimally invasive access could injuries of vessels or nerve structures larger than 1 mm in diameter be found. The authors did not encounter any problems when drilling open the articular surface with a destruction of 65% of the overall surface and when performing the following arthrodesis using a plug technique. Using a posterolateral, minimally invasive access between the Achilles tendon and lateral malleolus, it is possible to resect about 65% of the subtalar articular surface for arthrodesis without impact on major vessels and nerves. Postoperative complications such as sensitive and sensory failure as well as wound healing impairment at the lateral side of the foot are not to be expected when choosing the minimally invasive access.Conclusion It has to be said, however, that this technique does not offer the opportunity of performing a corrective arthrodesis as the hindfoot cannot be displayed during surgery. As the result of this study was positive, clinical evaluation was started.     

Arthrodesis of the wrist for osteoarthritis: outcome with a minimum follow-up of 4 years

The outcome of total wrist arthrodesis was reviewed in 36 patients with osteoarthritis after a minimum follow-up of 4 years. Pain relief was not complete, and although 20 were pain free at rest, only six were pain-free during manual activity. Grip strength was 63% of the contralateral side and the DASH score remained high. Only 21 of the 34 could be re-employed. The mean time off work was 14 months. Complications were numerous and additional surgery was required in 21 patients.     

Effect of intra-operative magnesium sulphate on pain relief and patient comfort after major lumbar orthopaedic surgery

The effects of intra-operative magnesium sulphate on pain relief after major lumbar surgery were investigated in 24 patients. Patients were randomly allocated to receive either an infusion of 50 mg x kg(-1) magnesium sulphate or an equivalent volume of saline at induction of anaesthesia. Anaesthesia was induced with propofol and remifentanil. Tracheal intubation was facilitated using rocuronium. Maintenance was achieved with remifentanil and sevoflurane in nitrous oxide/ oxygen. Intra-operative monitoring included standard equipment and neuromuscular transmission. During surgery, neuromuscular block recovery was longer in the magnesium group. Postoperative opioid consumption and pain scores were lower in the magnesium group. The first night's sleep and the global satisfaction scores were better in the magnesium group. The results of the study support magnesium sulphate as a useful adjuvant for postoperative analgesia after major lumbar surgery.     

A case of ankle osteoarthritis associated with lateral premalleolar bursitis caused by chronic ankle instability

IntroductionLateral premalleolar bursitis develops on the dorsolateral aspect of the foot anterior to the lateral malleolus, distinct from lateral malleolar bursitis located just around the lateral malleolus.Presentation of caseA 71-year-old woman visited an orthopedic clinic about 40 years after an episode of ankle sprain and was diagnosed with lateral premalleolar bursitis and osteoarthritis of the left ankle. Stress radiography revealed left ankle anterolateral malleolar bursitis with varus and anterior instability. We opted for less invasive arthroscopic ankle arthrodesis over open resection to stop the communication of the bursitis with the ankle joint. The lateral premalleolar bursitis was located just over the anterolateral portal. The remaining cartilage in the talotibial joint was removed and the subchondral surface was exposed and curetted down to a bleeding surface by ankle arthroscopy. The talotibial joint was fixed with 3 6.0-mm cannulated cancellous screws. The foot and ankle were immobilized by cast for 4 weeks. Bony union was achieved about 8 weeks postoperatively. The patient could perform daily activities without pain and with no recurrence of the lateral premalleolar bursitis at the 1.5-year follow-up.DiscussionTo our knowledge, this is the first report on arthroscopic arthrodesis for ankle osteoarthritis with recalcitrant lateral premalleolar bursitis caused by the check valve mechanism of chronic ankle instability after old ankle sprain.ConclusionWe report a case of arthroscopic arthrodesis for osteoarthritis of the ankle associated with lateral premalleolar bursitis caused by the check valve mechanism of chronic ankle instability after old ankle sprain.