Post-retrieval functionality testing of PRECICE lengthening nails: The “Sleeper” nail concept

IntroductionPRECICE intramedullary magnetic lengthening nails, introduced in 2011, have changed the landscape of long bone limb lengthening. The implants have a stroke ranging from 5 to 8 cm, but it may be desirable to perform part of the lengthening at one treatment, allow bone healing, leave the implant in place, dormant, and then return one or more years later to re-lengthen with the same implant. We call this the “sleeper” nail concept. This strategy may be gentler for the joints and soft tissues. Would the nail mechanism still be functional one or more years later?MethodsWe tested 102 intact, consecutively explanted nails. Using a “fast magnet,” the male part was lengthened to 5 mm short of its maximum stroke capacity and retracted back to 35 mm (all nails start with the male part exposed 30 mm). The nails passed the test if the male part succeeded in lengthening to 5 mm short of the maximum stroke capacity and back to 35 mm (or only retract in case fully deployed at testing). During our testing, the nails were prevented from reaching their full capacity of lengthening/retraction to avoid jamming the gears. Failure was defined as the inability or partial ability to complete the process.ResultsEighty-six nails (84.3%) performed successfully according to our testing standard. When comparing successful and failed nails in terms of nail type, generation, diameter, length and in vivo interval, there was no statistical significance. Comparing both groups in terms of status at testing (fully deployed or not) showed statistical significance with 9 of the 16 failed nails fully deployed at testing (p < 0.001).ConclusionDormant PRECICE nails can be reactivated for further lengthening. The results imply that full deployment may damage the mechanism, making future re-use by retracting and then re-lengthening unsuccessful. The candidate nails for this purpose should not have any signs of clear damage (bending or breakage) and should not have been fully deployed. However, surgeons and patients should be aware of the need for possible nail exchange if the “sleeper” nail fails to wake up.Level of evidenceLevel IV case series analysis of retrieved surgical implants.     

Longer Term Outcomes Following High Tibial Osteotomy for Osteoarthritis: A Prospective,Multi-Centre Observational Study Comparing Tomofix and OPTY-LINE Devices

PurposeAssessing surgical accuracy and patient-recorded outcome measures for patients fitted with either the OPTY-LINE intramedullary realignment system or the Tomofix plate for medial opening wedge high tibial osteotomy (HTO).Patients and methodsTwo matched case series of patients with symptomatic medial compartment osteoarthritis without other significant knee pathology. One group comprised of 19 patients receiving the Tomofix plate, whereas another comprised of 12 patients receiving the OPTY-LINE intramedullary nail. Patella-centred long leg alignment radiographs were assessed to calculate surgical accuracy in all cases. Patients completed knee injury osteoarthritis outcome scores (KOOS) and osteotomy surgery patient satisfaction questionnaires pre-operatively and at 24 months post-surgery.ResultsAbsolute surgical accuracy at 2 years post-surgery was a mean 4.2 [standard deviation 3.7] for OPTY-LINE versus 9.2 [SD 7.8] for Tomofix (p = 0.11, Mann–Whitney U test). On average, patients in either the OPTY-LINE or Tomofix cohort reported at least a minimal perceptible clinical improvement—minimum average improvement of 15—for all five KOOS themes. No significant difference in change of KOOS scores over time or patient satisfaction levels were observed between the two cohorts.ConclusionThe OPTY-LINE device for HTO performs to a similar level as the Tomofix device. Surgical accuracy data are promising for OPTY-LINE, but does not seem to readily translate into difference in patient-reported outcomes compared to Tomofix. Even longer follow-up periods, to measure survival rates, and true randomised trials on larger samples can elucidate if there is a benefit for using one device over the other.     

Analysis of factors among 30-day and 1-year mortality rates in patients with borderline stable-unstable intertrochanteric hip fracture

ObjectiveThis study aimed to evaluate the possible effects of surgical procedures on mortality and to identify the possible risk factors for mortality in the management of geriatric hip fractures.MethodsA total of 191 patients (105 women and 86 men; mean age 82.26±9.681 [60–108] years) with AO/OTA 31A2.2 intertrochanteric fractures and treated with sliding hip screw, proximal femoral nail, or hemiarthroplasty were included in this retrospective cohort study. The treatment type was decided by the responsible surgeon according to the patients’ pre-injury activity level, bone quality, and features of the fracture. Age, sex, type of fracture, type of surgery performed, American society of anesthesiology (ASA) grade, type of anesthesia, time to surgery, type of physical therapy, length of hospital stay, and number of comorbidities were documented. We evaluated the 30-day and 1-year mortality of patients treated with sliding hip screw (SHS), proximal femoral nail antirotation (PFN-A), or hemiarthroplasty and identified the possible risk factors for mortality.ResultsA total of 49 patients underwent SHS, 58 underwent PFN-A, and 84 underwent hemiarthroplasty. Of these, 2 patients with SHS, 2 with PFN-A, and 11 with hemiarthroplasty died within 30 days after surgery, whereas 7 patients with SHS, 15 with PFN-A, and 23 with hemiarthroplasty died 1 year after surgery. The 30-day and 1-year overall mortality rates were 7.9% and 23.6%, respectively. Both the 30-day and 1-year mortality risks were higher in patients undergoing hemiarthroplasty than in patients undergoing SHS (p=0.068 versus 0.058). The 30-day mortality was higher in patients receiving general anesthesia than in those receiving combined spinal and epidural anesthesia (p=0.009). The 1-year mortality risk was higher in patients with ASA grade 4 than in those with grade 1 and 2 (p=0.045). Advanced age (p=0.022) and male sex (p=0.007) were also found to be the risk factors for 1-year mortality.ConclusionWe demonstrated that higher ASA grade, male sex, general anesthesia, and hemiarthroplasty procedures are associated with higher mortality rates in elderly patients with hip fractures. Thus, we highly recommend orthopedic surgeons to consider all these factors in the management of intertrochanteric hip fractures in the geriatric population.Level of EvidenceLevel IV, Prognostic Study     

股骨近端髓内钉三维导航器的研制与测试

目的研发一种专用于防旋型股骨近端髓内钉置入时的三维导航器。方法选取颈干角为(135±5)°,并且股骨大转子顶点基本与股骨头中心等高的人体股骨骨骼的干标本32例,其中左侧16例,右侧16例。通过股骨头中心、平行于股骨干、垂直于股骨干与股骨颈所在的平面用钢锯将股骨标本的股骨头进行截骨;在股骨大粗隆顶端开口向股骨近端髓腔内插入PFNA主钉,主钉钉尾与股骨头中心点在同一高度上。在本课题所研发的股骨近端髓内钉三维导航器的导引下向股骨头颈部打入动力钉导引针,测量动力钉导引针在股骨头截骨面上的出针点与经股骨头中心点直线的垂直距离作为偏离值。结果利用本课题所研制的三维立体导航器在32例股骨骨骼的干标本上置入导引针,其中14例偏离值为0(占43.75%),最大偏离值为2mm,仅3例(占9.375%),平均误差只有0.69mm。结论本课题所研制的导航器结构简单,操作简便,定位精确,值得进一步在临床上研究应用。     

顺行交锁髓内钉治疗肱骨骨折

目的探讨顺行交锁髓内钉治疗肱骨骨折的手术要点和治疗效果。方法回顾性分析2003年10月～2005年10月23例顺行肱骨交锁髓内钉治疗肱骨干中上段骨折。结果全部病例随访6个月～1年3个月,平均11个月。所有病例均骨性愈合,平均临床愈合时间为2.4个月。所有关节活动度均可。结论顺行交锁髓内钉治疗肱骨中段或中上段骨折,效果良好。     

交锁髓内钉治疗胫骨不稳定性骨折

目的 探讨交锁髓内钉治疗胫骨不稳定骨折的效果。方法 本研究38例中不扩髓法31例,扩髓法7例;闭合穿针33例,开放穿针5例;静力性固定32例,动力性固定6例。结果 平均随访时间10月（3～22月）采用Johner-Wruh评分标准,对治疗的最终结果证定：优31例,良5例,中1例,差1例。骨折平均愈合时间;闭合性骨折16周（11～24周）,开放性骨折18周（12～26周）,2例延迟愈合（闭合性骨折、开放性骨折各1例）。无感染及骨不连。结论 文锁髓内钉是治疗胫骨不稳定骨折的较好方法之一。     

Gamma钉治疗股骨粗隆间骨折效果探讨

目的 探讨应用Gamma钉治疗股骨粗隆间骨折的疗效。方法 应用Gamma钉治疗我院骨科自1997年1月－2000年1月收治疗的各种股骨粗是骨折的患者36例。结果 本组病例经术后平均1年6个月的访,骨折愈合,无1例发生髋内翻、下肢外旋和短缩等畸形,患肢关节功能优良率88.4%,疗效较好。结论 Gamma钉是治疗股骨粗隆间骨折较为理想的方法。     

生长期儿童股骨干骨折髓内针内固定的远期观察

作者从1970～1985年收治生长期儿童股骨干骨折305例,其中切开复位髓内针内固定34例(38处股骨骨折),并进行了5～17年的长期随访观察,发现无1例出现术后早期并发症,12例(占33.3％)出现大粗隆发育受阻的晚期并发症。18例(22处股骨骨折)双下肢等长,13例患肢较健侧长0.8～1.4cm平均1.03cm,1例合并有下肢动脉损伤者出现下肢短缩。作者认为无论采用梅花型髓内针内固定,还是三棱型髓内针内固定都是可行的,但梅花型髓内针内固定有出现大粗隆发育受阻的危险。     

大段同种异体骨移植交锁髓内钉内固定修复四肢骨肿瘤切除后骨缺损

目的：探讨四肢骨肿瘤切除后采用大段异体骨移植交锁髓内钉内固定修复骨缺损的疗效。方法：1998年—2003年对18例例患者进行了病灶清除、交锁髓内钉内固定加同种异体骨移植术。结果：术后随访1～50月，2例死亡，其余16例接合区骨质生长良好，无1例骨发生不连接。肩、膝、踝关节活动及肢体负重良好。结论：本手术方法使固定节段具有高度的内在稳定性，可早期进行功能锻炼，防止影响肩、膝、踝关节的负重功能或防止创伤关节炎，适合于四肢骨肿瘤切除后骨缺损的修复。