Yaser M.K. Baghdadi

Total Elbow Arthroplasty in Obese Patients

BACKGROUND The prevalence of obesity in the United States has increased in recent decades. The aim of this study was to evaluate the influence of obesity in patients undergoing primary total elbow arthroplasty. METHODS From 1987 to 2006, 723 primary semiconstrained, linked total elbow arthroplasties were performed in 654 patients. The average patient age (and standard deviation) at the time of surgery was 62.3 ± 13.7 years, with 550 total elbow arthroplasties (76%) performed in women. Total elbow arthroplasties were used to treat inflammatory conditions in patients undergoing 378 total elbow arthroplasties (52%) and to treat acute traumatic or posttraumatic conditions in patients undergoing 310 total elbow arthroplasties (43%). Patients were classified as non-obese (having a body mass index of <30 kg/m2) in 564 total elbow arthroplasties (78%) and as obese (having a body mass index of ≥30 kg/m2) in 159 total elbow arthroplasties (22%). The median duration of follow-up was 5.8 years (range, zero to twenty-five years). Survivorship of total elbow arthroplasty was estimated with use of the Kaplan-Meier method. The effect of obesity on risk of total elbow arthroplasty revision was estimated with use of Cox regression models, adjusting for age, sex, body mass index, and indication. RESULTS A total of 118 revisions (16%) were performed. The ten-year survival rate for total elbow arthroplasty revision for any reason was 86% (95% confidence interval, 82% to 89%) in non-obese patients compared with 70% (95% confidence interval, 60% to 79%) in obese patients (p < 0.05). The ten-year survival rate for total elbow arthroplasty revision for mechanical failure was 88% (95% confidence interval, 84% to 91%) in non-obese patients compared with 72% (95% confidence interval, 61% to 81%) in obese patients (p < 0.05). Severely obese patients (those with a body mass index of 35 to <40 kg/m2) had a significantly higher risk of total elbow arthroplasty revision for any reason (hazard ratio, 3.08 [95% confidence interval, 1.61 to 5.45]; p < 0.05) and mechanical failure (hazard ratio, 3.10 [95% confidence interval, 1.47 to 5.89]; p < 0.05) compared with non-obese patients. CONCLUSIONS Obesity adversely influences the performance of elbow replacement after primary total elbow arthroplasty. Obese patients being considered for elbow replacement surgery should be counseled accordingly.

Sagittal balance and spinopelvic parameters after lateral lumbar interbody fusion for degenerative scoliosis: A case-control study

Study Design. Retrospective matched-cohort analysis. Objective. To evaluate the change in radiographical parameters in patients undergoing interbody fusion and posterior instrumentation compared with posterior spine fusion (PSF) alone for degenerative scoliosis. Summary of Background Data. Little is known about the effect of lateral interbody fusion (LIF) on sagittal plane correction in the setting of degenerative scoliosis. We performed a retrospective study to investigate these changes compared with PSF. Methods. Between 1997 and 2011, 33 patients had LIF at 181 levels between T8 and L5 vertebrae for the treatment of degenerative scoliosis (mean; 5 ± 2 levels). Of those, 23 patients had additional anterior lumbar interbody fusion (ALIF) at 37 levels between L4 and S1 vertebrae (mean; 1.6 ± 0.5 levels). A 1:1 matched control of patients who underwent PSF was performed. Patients were matched by age, sex, and diagnosis. Clinical and radiographical data were collected and compared between the matched cohorts. Results. Lumbar lordosis (LL) was significantly restored in the LIF ± ALIF compared with PSF cohort (44° ± 14° vs. 36° ± 15°, P = 0.02). The segmental LL over the 102 LIF levels significantly improved from 12°± 10° to 21°± 13° postoperatively (P < 0.0001). However, the change over the 37 ALIF levels was not significant (from 30° ± 15° to 29° ± 9°, P = 0.8). Sagittal plane alignment was improved in the LIF ± ALIF compared with PSF cohort and trended toward but did not reach significance (3.8 ± 3.2 cm vs. 6.2 ± 5.7 cm, P = 0.09). Sacral slope was significantly higher in the LIF ± ALIF compared with PSF cohort (33° ± 11° vs. 28° ± 10°, P = 0.03). Pelvic tilt was lower in the LIF ± ALIF compared with PSF cohort and trended toward but did not reach significance (22° ± 10° vs. 26° ± 10°, P = 0.08). Conclusion. LL and sacral slope had mildly but statistically improved in the interbody fusion cohort compared with PSF cohort. Sagittal alignment and pelvic tilt trended toward but did not reach statistical significance. Segmental LL was improved at LIF levels more than at ALIF levels. Level of Evidence: 3

Implant Distribution in Surgically Instrumented Lenke 1 Adolescent Idiopathic Scoliosis: Does It Affect Curve Correction?

Study Design. Retrospective review of prospective multicenter database of patients with adolescent idiopathic scoliosis who underwent posterior spinal fusion. Objective. To analyze implant distribution in surgically instrumented Lenke 1 patients and evaluate how it impacts curve correction. Summary of Background Data. Although pedicle screw constructs have demonstrated successful surgical results, the optimal pedicle screw density and configuration remain unclear. Methods. A total of 279 patients with adolescent idiopathic scoliosis treated with pedicle screws were reviewed. Implant density was computed for each side of the instrumented segment, which was divided into 5 regions: distal and proximal ends (upper/lower instrumented vertebra +1 adjacent vertebra), apical region (apex ± 1 vertebra), and the 2 regions in between (upper/lower periapical). Centralized measurement of Cobb angle and thoracic kyphosis was performed on preoperative and at 1-year postoperative radiographs as well as percent curve flexibility. Results. The mean implant density was 1.66 implants per level fused (1.08 to 2) with greater available pedicles filled on the concavity (92%, 53%–100%) compared with the convex side (73%, 23%–100%, P < 0.01). The concave distal end region had the highest density with 99% of pedicles filled (P < 0.01), followed by the other concave regions and the convex distal end region (88%–94%) (P > 0.05). Other convex regions of the construct had less instrumentation, with only 54% to 78% of pedicles instrumented (P < 0.01). Implant density in the concave apical region (69%, 23%–100%) had a positive effect on curve correction (P = 0.002, R = 0.19). Conclusion. Significant variability exists in implant distribution with the greatest variation on the convex side and lowest implant density used in the periapical convex regions. Only instrumentation at the concave side, particularly at the apical region, was associated with curve correction. This suggests that for a low implant density construct, the best regions for planned screw dropout may be in the periapical convexity. Level of Evidence: 3

Complications of pedicle screws in children 10 years or younger: a case control study.

Study Design. Case control study. Objective. To determine complications associated with pedicle screw use and screw accuracy in children 10 years or younger. Summary of Background Data. Pedicle screws are frequently used for the treatment of spine deformity in children, but, for young patients, this is only by physician-directed use. Thus, we sought to determine the rates of screw-related complications and screw malposition in patients 10 years or younger compared with a series of matched controls greater than 10 years of age. Methods. From 2000–2011, 265 screws were placed in 33 consecutive patients undergoing a total of 35 procedures for a variety of spine deformities. Mean age at surgery was 7 years (range, 2–10) with a mean time to follow-up of 3.3 ± 2.4 years. Congenital spine deformity was the most common surgical indication. Primary outcome measures were screw-related complication or return to surgery for screw malposition. Patients were matched by diagnosis/fusion level to 66 control patients greater than 10 years of age. Available computed tomographic scans in young children were reviewed to assess screw accuracy. Results. In patients 10 years or younger, 2 out of 265 screws (0.75%) resulted in a screw-related complication. No patient required revision surgery due to screw malposition. No patients older than 10 years in the matched controls had a screw-related complication or revision surgery due to screw malposition. Computed tomograpic data was available for 10 young patients, which was compared with data from the larger cohort of 81 older children. No difference was found in the rates of severe asymptomatic screw malposition, but moderate screw malposition was more common in the younger cohort. Conclusion. In this limited series, 265 pedicle screws were placed in 33 patients 10 years or younger with 0.75% of pedicle screws resulting in a complication. The rates of screw malposition revealed on computed tomographic scan were similar to those of adolescent children. These data support the use of pedicle screws in children 10 years or younger for the treatment of complex spinal deformity. Level of Evidence: 4

Total hip arthroplasty for the sequelae of Legg-Calvé-Perthes disease.

BackgroundThe durability and risks associated with total hip arthroplasty (THA) for patients with a history of Legg-Calvé-Perthes disease (LCPD) are not well known.Questions/purposeWe sought to (1) determine the survivorship of THAs performed for LCPD; (2) assess hip scores and complications associated with THA in this patient population; and (3) compare results between patients who had undergone surgery in childhood with patients who had conservative treatment.MethodsWe reviewed 99 primary THAs performed in 95 patients with a history of LCPD with minimum 2-year followup (mean ± SD, 8 ± 5 years). Mean age at THA was 48 ± 15 years.ResultsA total of 10 revisions were performed. Using revision for any reason as the end point, the 8-year survival rate was 90% (95% confidence interval [CI], 76%–96%) for cementless implants compared with 86% (95% CI, 57%–96%) for hybrid implants. The mean Harris hip score improved by 31 ± 16 (n = 76). Complications occurred in 16% of hips. The most common major complication was intraoperative fracture (eight femoral, one acetabular). Three patients developed sciatic nerve palsy after a mean lengthening of 2.2 ± 1 cm compared with a mean of 1.4 ± 1 cm in patients with intact sciatic nerve (p = 0.3).ConclusionsCementless THAs for the sequelae of LCPD demonstrate 90% survival from any revision at 8 years followup. THAs for the sequelae of LCPD can be complicated and technically difficult. Intraoperative fractures and nerve injuries are common. Care should be taken to avoid excessive limb lengthening.Level of EvidenceLevel IV, retrospective case series. See Guidelines for Authors for a complete description of levels of evidence.

Primary Linked Semiconstrained Total Elbow Arthroplasty for Rheumatoid Arthritis: A Single-Institution Experience with 461 Elbows Over Three Decades

BACKGROUND Elbow arthroplasty is the treatment of choice for end-stage rheumatoid arthritis (RA). The purpose of this study was to determine the long-term outcome of a linked semiconstrained elbow arthroplasty implant design in patients with RA. METHODS Between 1982 and 2006, 461 primary total elbow arthroplasties using the Coonrad-Morrey prosthesis were performed in 387 patients with RA. Fifty-five of the arthroplasties were performed to treat concurrent traumatic or posttraumatic conditions. There were 305 women (365 elbows, 79%) and 82 men (96 elbows, 21%). Ten patients (10 elbows) were lost to follow-up, 9 patients (10 elbows) died, and 6 patients (6 elbows) underwent revision surgery within the first 2 years. For the 435 elbows (362 patients, 94%) with a minimum of 2 years of follow-up, the median follow-up was 10 years (range, 2 to 30 years). RESULTS At the most recent follow-up, 49 (11%) of the elbows had undergone component revision or removal (deep infection, 10 elbows; and mechanical failure, 39 elbows). Eight additional elbows were considered to have radiographic evidence of loosening. For surviving implants followed for a minimum of 2 years, the median Mayo Elbow Performance Score (MEPS) was 90 points. Bushing wear was identified in 71 (23%) of the surviving elbows with a minimum of 2 years of radiographic follow-up; however, only 2% of the elbows had been revised for isolated bushing wear. The rate of survivorship free of implant revision or removal for any reason was 92% (95% confidence interval [CI] = 88% to 94%) at 10 years, 83% (95% CI = 77% to 88%) at 15 years, and 68% (95% CI = 56% to 78%) at 20 years. The survivorship at 20 years was 88% (95% CI = 83% to 92%) with revision due to aseptic loosening as the end point and 89% (95% CI = 77% to 95%) with isolated bushing exchange as the end point. Risk factors for implant revision for any cause included male sex, a history of concomitant traumatic pathology, and implantation of an ulnar component with a polymethylmethacrylate surface finish. CONCLUSIONS Elbow arthroplasty using a cemented linked semiconstrained elbow arthroplasty provides satisfactory clinical results in the treatment of RA with a reasonable rate of survivorship free of mechanical failure at 20 years. Although bushing wear was identified on radiographs in approximately one-fourth of the patients, revision for isolated bushing wear was uncommon. LEVEL OF EVIDENCE Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

At What Levels Are Freehand Pedicle Screws More Frequently Malpositioned in Children

STUDY DESIGN Retrospective case series. BACKGROUND Previous studies report that 5% to 17% of pedicle screws placed in children are malpositioned. Knowledge of the long-term effects of malpositioned screws is limited. We sought to further characterize risk factors for malpositioned pedicle screws in order to establish a more proactive role in limiting future complications. OBJECTIVE We undertook this study to answer the following: 1) Is the rate of freehand pedicle screw malpositioning higher in children with spinal deformity, particularly at the apical concavity? 2) At what vertebral levels do freehand pedicle screws have the highest rates of malpositioning? 3) In which direction (medial or lateral) do freehand pedicle wall violations occur most often? METHODS Incidental postoperative computed tomographic (CT) exams were retrospectively reviewed in 85 pediatric patients (605 screws) treated with posterior spinal fusion using freehand pedicle screw technique. Of the screws imaged, 355 were in patients without deformity and 250 in patients with deformity. Breaches were categorized as mild (<2 mm), moderate (2-4 mm), or severe (>4 mm). RESULTS Screws in pediatric deformity patients were more frequently malpositioned by 2 mm or more than were screws in patients without deformity (26% vs. 19%, p = .02). In patients with deformity, no higher rate of screw malposition was detected at the apical region. Overall, the highest rates of severe screw malposition were between T3 and T8. Pedicle breaches were more commonly in a medial direction compared with lateral (74% vs. 26%, p < .0001). However, severe breaches within the T3-T8 region were more often directed lateral than medial (92% vs. 8%, p ≤ .0001). CONCLUSIONS The clinical significance of asymptomatic pedicle screw breaches in children has not yet been determined. In this study, screws at the apical concavity were no more likely to be malpositioned than those at other sites. Efforts to reduce pedicle screw malposition would likely be most effective at the T3-T8 levels. LEVEL OF EVIDENCE Level IV, Therapeutic Study. See the Guidelines for Authors for a complete description of the levels of evidence.

Long-term outcomes of gastrografin in small bowel obstruction

BACKGROUND The gastrografin (GG) challenge is a diagnostic and therapeutic tool used to treat patients with small bowel obstruction (SBO); however, long-term data on SBO recurrence after the GG challenge remain limited. We hypothesized that patients treated with GG would have the same long-term recurrence as those treated before the implementation of the GG challenge protocol. METHODS Patients ≥18 years who were treated for SBO between July 2009 and December 2012 were identified. We excluded patients with contraindications to the GG challenge (i.e., signs of strangulation), patients having SBO within 6-wk of previous abdominal or pelvic surgery and patients with malignant SBO. All patients had been followed a minimum of 1 y or until death. Kaplan-Meier method and Cox regression models were used to describe the time-dependent outcomes. RESULTS A total of 202 patients were identified of whom 114 (56%) received the challenge. Mean patients age was 66 y (range, 19-99 y) with 110 being female (54%). A total of 184 patients (91%) were followed minimum of 1 year or death (18 patients lost to follow-up). Median follow-up of living patients was 3 y (range, 1-5 y). During follow-up, 50 patients (25%) experienced SBO recurrences, and 24 (12%) had exploration for SBO recurrence. The 3-year cumulative rate of SBO recurrence in patients who received the GG was 30% (95% confidence interval [CI], 21%-42%) compared to 27% (95% CI, 18%-38%) for those who did not (P = 0.4). The 3-year cumulative rate of exploration for SBO recurrence in patients who received the GG was 15% (95% CI, 8%-26%) compared to 12 % (95% CI, 6%-22%) for those who did not (P = 0.6). CONCLUSIONS The GG challenge is a clinically useful tool in treating SBO patients with comparable long-term recurrence rates compared to traditional management of SBO.

Reply to the letter to the editor: anconeus interposition arthroplasty: mid- to long-term results.

We would like to thank Dr. van den Bekerom and colleagues for their letter regarding our recently published paper [1]. Their comments were insightful and will benefit many readers. We agree with van den Bekerom and colleagues’ comments that comparing the clinical results of anconeus interopsition arthroplasty to the results of other surgical treatments (radiocapitellar prosthetic arthroplasty or simple radial head resection) will provide stronger evidence than we reported in our current study [1]. However, we state that the anconeus arthroplasty can serve as an option for situations in which these other interventions are not feasible for any of several reasons. Each patient included in our series had been independently evaluated for best available option to address their radiocapitellar arthritis and/or proximal radioulnar impingement. Given that these patients had been treated with anconeus arthroplasty during a wide study period (between 1992 and 2012) other alternatives to anconeus arthroplasty might not have been available at the time of patient presentation. Additionally, these patients mostly were young and largely underwent the interposition to address a multifactorial elbow symptoms rather than an isolated problem in the context of multiple previous interventions; 14 patients (48%) in this group had at least two prior operations on the affected elbow. Furthermore, since these patients generally were rather young, we try to avoid prosthetic replacement because of concerns with the unresurfaced capitellar side of the joint at the long term, as well as mechanical failure of a radial head implant secondary to loosening [3]. Also the current long-term reports are insufficient to support the radiocapitellar prosthetic arthroplasty [2]. Finally, as noted in our study limitations, the latest radiographs were not available for all patients and the radiographic followup duration was obviously shorter in comparison to the followup of patient outcome scores. Thus, it would be difficult to correlate any radiographic parameters, including proximal migration of the radius, with outcomes scores, since the information or each of these two measures was collected at different time point.

The hospital cost of two-stage reimplantation for deep infection after shoulder arthroplasty

Background The cost of treating infection after hip and knee arthroplasty is well documented in the literature. The purpose of this study was to determine the cost of two-stage reimplantation for deep infection after shoulder arthroplasty. Methods Between 2003 and 2012, 57 shoulders (56 patients) underwent a two-stage reimplantation for deep periprosthetic shoulder infection; implants placed at reimplantation included anatomic total shoulder arthroplasty (a-TSA) in 58%, reverse total shoulder arthroplasty (r-TSA) in 40%, and hemiarthroplasty (HA) in 2%. During the same timeframe, 2953 primary shoulder arthroplasties (2589 patients) were performed at the same institution (a-TSA in 55%, r-TSA in 28%, and HA in 17%). Total direct medical costs were calculated by using standardized, inflation-adjusted costs for services and procedures billed during hospitalization and were adjusted to nationally representative unit costs in 2013 inflation-adjusted dollars. Results The mean hospital cost (per shoulder) for two-stage reimplantation was