Determinants of evolution of endplate and disc degeneration in the lumbar spine: a multifactorial perspective.

Purpose: Evolution and progression of disc and endplate bone marrow degeneration of the lumbar spine are thought to be multifactorial, yet, their influence and interactions are not understood. The aim of this study was to find association of potential predictors of evolution of degeneration of the lumbar spine.

Methods: Patients (n = 90) who underwent two lumbar magnetic resonance imaging (MRI) exams with an interval of at least 4 years and without any spinal surgery were included into the longitudinal cohort study with nested case-control analysis.

Tendon response to pharmaco-mechanical stimulation of the chronically retracted rotator cuff in sheep.

Purpose: Chronic tearing of tendons is associated with molecular and structural alterations causing biomechanical changes, which compromise musculotendinous function and become limiting factors for tendon repair. This study investigated the histological response of chronically retracted sheep rotator cuff tendons to mechanical and pharmacological stimulation in view of tendon repair.

Methods: Sixteen weeks after experimental release of the infraspinatus tendon in 20 sheep, the retracted musculotendinous unit was subjected to continuous traction either with [anabolic steroids (nandrolone) group/insulin-like growth factor (IGF) group] or without (control group) additional pharmacological treatment during 6 weeks.

Is an annular tear a predictor for accelerated disc degeneration?

Purpose: It is questionable whether an annular tear (AT) is a predictor for accelerated degeneration of the intervertebral discs. The aim of the present study was to answer this question via a matched case-control study design that reliably eliminates potential confounders.

Materials: Presence or absence of AT, defined as a hyperintense lesion within the annular fibrosus on T2-weighted non-contrast MRI images, was documented in 450 intervertebral lumbar discs of 90 patients who could be followed up for at least 4 years with MRI.

The primer for sports medicine professionals on imaging: the shoulder.

Because of its inherent superior soft tissue contrast and lack of ionizing radiation, magnetic resonance imaging (MRI) is highly suited to study the complex anatomy of the shoulder joint, particularly when assessing the relatively high incidence of shoulder injuries in young, athletic patients. This review aims to serve as a primer for understanding shoulder MRI in an algorithmical approach, including MRI protocol and technique, normal anatomy and anatomical variations of the shoulder, pathologic conditions of the rotator cuff tendons and muscles, the long head of the biceps tendon, shoulder impingement, labral and glenohumeral ligament pathology, MR findings in shoulder instability, adhesive capsulitis, and osteoarthritis.

Associations between lumbosacral transitional anatomy types and degeneration at the transitional and adjacent segments.

Background Context: The relation between specific types of lumbosacral transitional vertebra and the degree of degeneration at and adjacent to the transitional level is unclear. It is also unknown whether the adjacent cephalad segment to a transitional vertebra is prone to greater degeneration than a normal L5-S1 level.

Purpose: The purpose of this study was to evaluate the relation between specific lumbosacral transitional vertebra subtypes according to the Castellvi classification, and to determine the severity of degeneration at the transitional level and the adjacent cephalad segment.

Interreader and intermodality reliability of standard anteroposterior radiograph and magnetic resonance imaging in detection and classification of lumbosacral transitional vertebra.

Background Context: Different types of lumbosacral transitional vertebra (LSTV) are classified based on the relationship of the transverse process of the last lumbar vertebra to the sacrum. The Ferguson view (30° angled anteroposterior [AP] radiograph) is supposed to have a sufficient interreader reliability in classification of LSTV, but is not routinely available. Standard AP radiographs and magnetic resonance imaging (MRI) are often available, but their reliability in detection and classification of LSTV is unknown.

Latissimus dorsi tendon transfer for treatment of irreparable posterosuperior rotator cuff tears: long-term results at a minimum follow-up of ten years.

Background: Transfer of the latissimus dorsi tendon to the greater tuberosity of the humerus for treatment of an irreparable rotator cuff tear has been reported to yield good-to-excellent short to intermediate-term results in well-selected patients. The purpose of this study was to evaluate the long-term outcome of such transfers for irreparable posterosuperior rotator cuff tears to determine the durability of the results and to identify risk factors for an unfavorable outcome.

Methods: Fifty-seven shoulders in fifty-five patients (seventeen women and thirty-eight men with a mean age of fifty-six years) were managed with latissimus dorsi tendon transfer.

Multiple myeloma exacerbation following utilization of bone morphogenetic protein-2 in lateral lumbar interbody fusion: a case report and review of the literature.

Background Context: Recent studies generated antithetic results regarding the safety of bone morphogenetic protein-2 (BMP-2) use in spine surgery, and the effect of this biologic adjunct on myeloma cells remains to be fully elucidated.

Purpose: The purpose of this study was to present a case of multiple myeloma (MM) exacerbation after BMP-2 implantation in the setting of lateral lumbar interbody fusion (LLIF).

Study Design: Case report and literature review.

A novel technique for detecting instability of the distal radioulnar joint in complete triangular fibrocartilage complex lesions.

We performed this study to investigate whether discrepancy of bilateral dorsovolar shift of the distal radioulnar joint (DRUJ) is decisive for the diagnosis of DRUJ instability. Although several cadaver studies have quantified the amount of physiological dorsovolar shift, so far, there is no reliable method of quantification of DRUJ mobility in daily practice. The aim was to describe a novel sonographic method of quantifying DRUJ instability and evaluate its reliability and validity.

Asymmetry of the multifidus muscle in lumbar radicular nerve compression.

Objective: The multifidus muscle is the only paraspinal lumbar muscle that is innervated by a single nerve root. This study aimes to evaluate if the asymmetry of the multifidus muscle is related to the severity of compression of the nerve root or the duration of radiculopathy.

Methods: MRI scans of 79 patients with symptomatic single level, unilateral, lumbar radiculopathy were reviewed for this retrospective case series with a nested case-control study.

Imaging of acute cervical spine trauma: when to obtain which modality.

The current knowledge and evidence around the merits of different imaging modalities for the evaluation of cervical spine injuries are reviewed. The National Emergency X-Radiography Use Study, Canadian Cervical Spine rule, and American College of Radiology appropriateness criteria are reviewed and summarized. The advantages and disadvantages of available imaging modalities for selected cervical spine injury patterns are also illuminated to simplify the decision making on when to use which modality.

Deltoid muscle shape analysis with magnetic resonance imaging in patients with chronic rotator cuff tears.

Background: It seems appropriate to assume, that for a full and strong global shoulder function a normally innervated and active deltoid muscle is indispensable. We set out to analyse the size and shape of the deltoid muscle on MR-arthrographies, and analyse its influence on shoulder function and its adaption (i.e.

Operative treatment of chronic irreparable Achilles tendon ruptures with large flexor hallucis longus tendon transfers.

Background: Transfer of the flexor hallucis longus (FHL) tendon aims to restore function and relieve pain in chronic Achilles tendon (AT) disease. The goal of the present study was to investigate the clinical and radiographic outcomes of FHL transfer to the AT and to compare the transtendinous technique to the transosseous technique. We hypothesized that the type of technique would have a notable impact on outcome.

Diagnostic performance of MRI measurements to assess hindfoot malalignment. An assessment of four measurement techniques.

Objective: To investigate the ability of coronal non-weight-bearing MR images to discriminate between normal and abnormal hindfoot alignment.

Methods: Three different measurement techniques (calcaneal axis, medial/lateral calcaneal contour) based on weight-bearing hindfoot alignment radiographs were applied in 49 patients (mean, 48 years; range 21-76 years). Three groups of subjects were enrolled: (1) normal hindfoot alignment (0°-10° valgus); (2) abnormal valgus (>10°); (3) any degree of varus hindfoot alignment.

Partial supraspinatus tears are associated with tendon lengthening.

Purpose: Tendon tear may result in muscular retraction with the loss of contractile amplitude and strength of the rotator cuff muscles. Currently, neither a validated method of measuring supraspinatus tendon length nor normal values are known. It was therefore the purpose of this study to measure the normal length of the supraspinatus tendon and to determine whether partial tears are associated with changes in tendon length.

Bilateral diffuse pigmented villonodular synovitis of the knee.

Pigmented villonodular synovitis (PVNS) is a proliferative disease of synovial tissue characterized by lipid-laden macrophages, multinucleated giant cells, and hemosiderin deposits. PVNS presents either in a localized form with minimal rates of recurrence after surgical resection or in a diffuse form with an expansive growth pattern showing formation of osseous erosions and extra-articular manifestation. In the diffuse form high recurrence rates occur as a result of the challenge of achievement of total synovectomy.

Late Implant Removal After Posterior Correction of AIS With Pedicle Screw Instrumentation-A Matched Case Control Study With 10-Year Follow-up.

Study Design: Matched case-control study.

Objective: To find the amount of progression of deformity and its clinical consequences in the long term after implant removal (IR) as a result of late infection in adolescent idiopathic scoliosis (AIS).

Background Summary: Late IR is occasionally necessary after instrumented posterior correction of AIS because of late implant infection or implant-associated pain.

Posterior correction of thoracic adolescent idiopathic scoliosis with pedicle screw instrumentation: results of 48 patients with minimal 10-year follow-up.

Purpose: Since early 1990s pedicle screws in thoracic spine have been used in posterior correction of adolescent idiopathic scoliosis (AIS). Long-term results are scarce. We report clinical, radiological and pulmonary function results of 48 consecutive patients with 10-year minimal follow-up.

Does subacromial injection of a local anesthetic influence strength in healthy shoulders?: a double-blinded, placebo-controlled study.

Background: Subacromial injection of a local anesthetic is used to eliminate pain as a confounding factor in clinical assessment of abduction strength in shoulders with a suspected rotator cuff tear. If strength remains diminished despite pain relief, a rotator cuff tear is likely. The effect of injecting local anesthetic into the subacromial space on the strength of a normal shoulder is unknown, although it could affect strength by impairing suprascapular or axillary nerve function.

Rotator cuff muscles lose responsiveness to anabolic steroids after tendon tear and musculotendinous retraction: an experimental study in sheep.

Background: Long-standing rotator cuff tendon tearing is associated with retraction, loss of work capacity, irreversible fatty infiltration, and atrophy of the rotator cuff muscles. Although continuous musculotendinous relengthening can experimentally restore muscular architecture, restoration of atrophy and fatty infiltration is hitherto impossible.

Hypothesis: Continuous relengthening with pharmacological stimulation of muscle growth using an anabolic steroid or insulin-like growth factor (IGF) can reverse atrophy and fatty infiltration as well as improve the work capacity of chronically retracted rotator cuff muscles in sheep.

Suture slippage in knotless suture anchors as a potential failure mechanism in rotator cuff repair.

Purpose: To quantify the strength of suture fixation of knotless suture anchors in relation to the anchors' pullout strength and to compare these results with the static friction between different sutures and anchor materials.

Methods: Suture slippage within the anchor and pullout strength of 4 different knotless suture anchor models were assessed in a bovine bone model. Furthermore, the peak force before onset of slippage of different sutures trapped between increasingly loaded 4-mm rods made of commonly used anchor material (polyetheretherketone, poly-L-lactide acid, metal) was assessed.

Retraction of supraspinatus muscle and tendon as predictors of success of rotator cuff repair.

Background: The structural failure rate of rotator cuff repair can exceed 50%. Important predictors for repair failure are preoperative fatty muscle infiltration and myotendinous retraction.

Purpose: To quantitatively assess the prognostic value of preoperative retraction of both the supraspinatus muscle and tendon for the outcome of supraspinatus repair.

Revision of reversed total shoulder arthroplasty. Indications and outcome.

Background: The complications of reversed total shoulder arthroplasty (RTSA) requiring an additional intervention, their treatment options and outcome are poorly known. It was therefore the purpose of this retrospective study, to identify the reasons for revision of RTSA and to report outcomes.

Methods: Four hundred and forty-one performed RTSA implanted between 1999 and 2008 were screened.

Stitch positioning influences the suture hold in supraspinatus tendon repair.

Purpose: This study was designed to compare the pull-out strength of simple suture stitches in human supraspinatus tendons with respect to the position of the rotator cable.

Methods: Fifty-four tests were performed on 6 intact, human supraspinatus tendons, to assess the cutout strength of a simple suture configuration in different positions; medial to, lateral to, or within the rotator cable. Tendon thickness was measured and correlated for each positioned suture.