Purpose and Background

Both overall spine shape and the size and shape of individual vertebrae undergo rapid growth and development during early childhood. Motor development milestones such as age of walking influence spine development, with delayed ambulation linked with spinal conditions including spondylolysis. However, it is unclear whether associations between motor development and spine morphology persist into older age. Therefore, these associations were examined using data from the MRC National Survey of Health and Development, a large nationally-representative British cohort, followed up since birth in 1946.

Aims

Despite declining frequency of blood transfusion and electrolyte supplementation following total joint arthroplasty, postoperative blood analyses are still routinely ordered for these patients. This study aimed to determine the rate of blood transfusion and electrolyte restoration in arthroplasty patients treated with a perioperative blood conservation protocol and to identify risk factors that would predict the need for transfusion and electrolyte supplementation.

Total hip arthroplasty (THA) continues moving to the outpatient arena, and may be feasible for some conversion and revision scenarios. Controversy surrounds appropriate patient selection. The purpose of this study is to report complications associated with outpatient revision and conversion THA, and to determine if comorbidities are associated with complications or overnight stay.

From June 2013 through March 2018, 43 patients (44 hips) underwent conversion (n=12) or revision (n=32) THA at a free-standing ambulatory surgery center. Mean patient age was 58.4 years, and 52% of patients were male. Conversion procedures were for failed resurfacing in two, failed hemiarthroplasty in one, and failed fracture fixation with retained hardware in 9. Revision procedures involved head only in one, head and liner in 20, cup and head in 7, stem only in 2, and stem and liner in 2.

Forty-four (93%) were discharged same day without incident, none required transfer to acute facility, and 3 required overnight stay with 2 of these for convenience and only one for a medical reason, urinary retention. Three patients with early superficial infection were successfully treated with oral antibiotics. There were no major complications, readmissions, or subsequent surgeries within 90 days. One or more major comorbidities were present in 17 patients (39%) including 1 valvular disease, 8 arrhythmia, 2 thromboembolism history, 3 obstructive sleep apnea, 6 chronic obstructive pulmonary disease, 2 asthma, 4 frequent urination, and 1 renal disease. The single patient who stayed overnight for a medical reason had no major medical comorbidities.

Outpatient arthroplasty, including revision THA in some scenarios, is safe for many patients. Presence of medical comorbidities was not associated with risk of complications. The paradigm change of patient education, medical optimization, and a multimodal program to mitigate risk of blood loss and reduce need for narcotics facilitates performing arthroplasty safely in an outpatient setting.

Purpose

To investigate associations between sagittal thoracolumbar spine shape with sex and measures of adiposity throughout adulthood.

We systematically reviewed all the evidence published in the English language on proximal interphalangeal joint (PIPJ) replacement, to determine its effectiveness on the function of the hand and the associated post-operative complications.

Original studies were selected if they reported clinical outcome with a minimum of one year’s follow-up. Quality was assessed using the Cowley systematic review criteria modified for finger-joint replacements. Of 319 articles identified, only five were adequately reported according to our quality criteria; there were no randomised controlled trials. PIPJ replacements had a substantial effect size on hand pain of -23.2 (95% confidence interval (CI) -27.3 to -19.1) and grip strength 1.2 (95% CI -10.7 to 13.1), and a small effect on range of movement 0.2 (95% CI -0.4 to 0.8). A dorsal approach was most successful. Post-operative loosening occurred in 10% (95% CI 3 to 30) of ceramic and 12.5% (95% CI 7 to 21) of pyrocarbon replacements. Post-operative complications occurred in 27.8% (95% CI 20 to 37).

We conclude that the effectiveness of PIPJ replacement has not been established. Small observational case studies and short-term follow-up, together with insufficient reporting of patient data, functional outcomes and complications, limit the value of current evidence.

We recommend that a defined core set of patients, surgical and outcome data for this intervention be routinely and systematically collected within the framework of a joint registry.

With increased use of alternative bearings, surgeons have moved from utilization of 22, 26, 28 and 32mm heads to larger head diameters in total hip arthroplasty (THA). Reported benefits of large heads are enhanced stability secondary to the increased range of motion prior to impingement and the increased jump distance required for subluxation from the acetabulum.

This study evaluates the use of large diameter heads in primary THA comparing the rate of dislocation to a published study from our practice as a historic control.

Between October of 2001 and October 2008, 2015 THA with large heads were performed in 1743 patients. Femoral head sizes ranged from 36 to 60mm, with articulations consisting of metal-on-poly, ceramic-on-poly, and metal-on-metal. Operative approach was 63% less invasive direct lateral, 10% anterior supine intermuscular, and 27% standard direct lateral. In 1999 (Mallory et al., Clin Orthop Relat Res) we reported a low incidence of 12 dislocations (0.8%) in 1518 primary THA done with smaller femoral heads via a standard direct lateral approach. In the current series with large heads, follow-up averaged 22 months. There has been one dislocation requiring revision (0.05%), representing a significant reduction from our earlier report (p=0.0003). Forty additional acetabular components have been revised (2.0%), with eight related to sepsis (0.4%), 23 aseptic loosening (1.1%), six metal sensitivity (0.2%), one pseudotumor (0.05%), one failure of ingrowth (0.05%), and one acute early migration (0.05%).

The use of larger diameter heads has significantly lowered our dislocation rate in primary THA with only one occurrence observed in 2015 cases, for a rate of 0.05% at two years average follow-up.

Lateral retinacular release (LRR) may be necessary to balance the patellofemoral articulation in primary total knee arthroplasty (TKA). However, lateral retinacular release may be associated with an increased risk of patellar necrosis, loosening, perioperative bleeding, and pain.

Additionally, the need for lateral retinacular release may herald a more significant problem with implant positioning, rotation, and balance. The purpose of this study is to report the lateral retinacular release rate with a “patella friendly” femoral TKA design, and to identify if a less invasive approach is associated with reduced need for lateral retinacular release.

A retrospective review of our database identified 4667 primary TKA performed by two surgeons between October 2002 and January 2009. Beginning in 2002, a less invasive approach has been used in over 95% of primary TKA. Also beginning in 2002, the authors began using a new TKA design with a more swept back patellofemoral articulation (Vanguard Complete Knee System; Biomet). During the first two years of the study, the authors also used the Maxim Complete Knee System (Biomet). We previously reported a lateral retinacular release rate associated with the Maxim of 22%. There were 555 Maxim and 4112 Vanguard TKA performed. Lateral retinacular release with Maxim TKA was 12.8% (71/555), significantly less than that previously reported for the same implant design using a standard approach. Lateral retinacular release for Vanguard TKA was 1.8% (72/4112), significantly less than that with the Maxim TKA using either a standard or less invasive approach (p< 0.005).

Implant design, surgical technique, and a less invasive exposure combine to significantly reduce the need for lateral retinacular release in primary TKA.

Surgeons theorize smaller increments in sizing might better address different sized femurs and size differences between genders. This study examines utilisation of intermediate sized components to determine if availability affects outcomes of women and men undergoing total knee arthroplasty (TKA).

We reviewed 1903 consecutive, primary TKA in 1519 patients (64% women) performed with a single implant system. Originally, six femoral sizes were available; four intermediate sizes were added later. The system allows interchange ability of all femoral and tibial sizes and has seven constraint options. Four hundred and five TKA were done prior to intermediate size availability. In women before, 49% were 65mm, 47% 60mm, and 3% 70mm. After, 32% were 62.5mm, 21% 65mm and 8% 67.5mm. In men, 70mm was the most common representing 49% before and 41% after. The 65mm in men dropped from 29% before to 16% after and the 75mm dropped from 21% to 14%. After, 23% were 67.5mm. Minimum follow-up was two years.

When comparing women before versus after, women after had significantly better postoperative Knee Society (KS) pain (p=0.0000), clinical (p=0.003) and function scores (p=0.0000), and improvement in clinical (p=0.0000) and function scores (p=0.0001) while improvement in pain score was similar. Men done after had better postoperative KS pain (p=0.02) and function scores (p=0.002), and improvement in KS clinical (p=0.001) and function (p=0.0002) scores.

Both men and women undergoing TKA after availability of half sizes had better postoperative KS pain, clinical and functional scores, and improvement from preoperative levels compared with men and women before. We conclude a single TKA system with a wide variety of sizing and constraint options can provide consistently excellent results for both men and women undergoing TKA.

Reliable soft tissue attachment to prosthetic implants remains a great clinical challenge in adult reconstruction and oncology. Past efforts using tendon alone have been universally disappointing. With the introduction of trabecular metals, new possibilities present them selves in dealing with this problem. Using an established canine supraspinatus tendon model, reliable and physiologic soft tissue attachment to a trabecular metal prosthesis was achieved, with near normal strength and function. This suggests that this new genre of material can possibly provide better options in dealing with this difficult problem.

Direct attachment of tendon to an endoprothesis has applications throughout the field of orthopaedics. The purpose of this study was to devise a soft-tissue attachment device using tantalum foam metal which would allow for early soft tissue reconstruction strength and long term biologic in-growth fixation.

A foam metal tendon attachment prosthesis was designed. Using a validated tendon attachment model, twenty-three skeletally-mature canine supraspinatus tendons were sharply detached and then reattached to the greater tuberosity. Ultimate strength, stiffness and gross morphological changes were recorded immediately after surgery and at three and six weeks.

Tendon-implant strength as percent of normal rose from thirty-nine percent at surgery, to sixty-seven percent at three weeks, and ninety-nine percent at six weeks (standard deviations thirteen, nineteen, and eighteen percent). Stiffness of construct also approached normal tendon: forty-seven percent at surgery, sixty-two percent at three weeks, and ninety-four percent at six weeks (standard deviations seventy-seven, nineteen, and eighteen percent). Supraspinatus muscle volume decreased from ninety seven (percent of normal) at surgery, to seventy-nine percent at three weeks. By six weeks, the muscle had recovered to ninety percent of normal volume. Gross and histologic analysis revealed complete tendon in-growth and attachment to the prosthesis with the formation of Sharpey’s fibers

This study suggests that tendon attachment to a metallic endoprothesis is possible. Near normal physiologic strength and stiffness was achieved six weeks post surgery. Future study should ascertain the micro-anatomy of this attachment and delineate the mechanical conditions necessary for soft tissue in-growth.

Funding: Zimmer, Inc., Warsaw, IN

Please contact author for pictures, graphs and diagrams.

1. A case of metaphysial dysplasia observed for eleven years is reported.

2. Only one case with similar features has previously been reported.

3. The literature on the subject is reviewed.