Preventing Loss of Femoral Periprosthetic Bone Mineral Density in Cementless Total Hip Arthroplasty Using a Tapered Wedge Stem: A Retrospective, Cohort Study in Osteoporotic Patients Treated with Denosumab.

Purpose: Bone quality is an important issue in elderly osteoporotic patients who undergo total hip arthroplasty (THA) because periprosthetic fracture or aseptic loosening of implant caused by periprosthetic bone loss is a serious concern. Denosumab has been approved for osteoporosis patients. Thus, the purpose of this study was to investigate whether denosumab prevents loss of proximal femoral periprosthetic bone mineral density (BMD) in cementless THA using a tapered wedge stem in patients with osteoporosis. Methods: Seventy consecutive patients who had undergone primary THA were included in this study. Twenty-seven patients who received denosumab for osteoporosis formed the denosumab group, and 43 patients without denosumab formed the control group. Bone turnover markers and femoral periprosthetic BMD were measured at two weeks, six months, and 12 months after THA. BMD was evaluated in seven regions of interest according to the zones of Gruen. Results: BMD in zone 1 was significantly increased from baseline at both six and 12 months after THA in the denosumab group (10.0±10.2%, p<0.001 and 13.1±12.7%, p<0.001, respectively) and significantly decreased in the control group (-3.6±9.7%, p<0.05, and -5.9±9.4%, p<0.001, respectively). BMD in zone 7 was significantly decreased compared to baseline at both six and 12 months after THA in the control group (-19.2±20.2%, p<0.001 and -22.3±16.8%, p<0.001, respectively) but not in the denosumab group (-0.7±18.5% and -1.1±16.6%, respectively). The use of denosumab for THA patients with osteoporosis was independently related to preventing loss of periprosthetic BMD of the femur at 12 months after surgery in zones 1 (p<0.001) and 7 (p<0.001) on multivariate analysis. Conclusions: Denosumab significantly increased proximal femoral periprosthetic BMD in zone 1 and prevented loss of BMD in zone 7 in patients with osteoporosis after cementless THA using a tapered wedge stem at both seven and 12 months. Future studies of denosumab treatment following THA in patients with osteoporosis should focus on clinical outcomes such as the risk of periprosthetic fracture and revision THA.

Neurological Analysis Based on the Terminal End of the Spinal Cord and the Narrowest Level of Injured Spine in Thoracolumbar Spinal Injuries.

This study aimed to clarify neurological differences among the epiconus, conus medullaris, and cauda equina syndromes. Eighty-seven patients who underwent surgery for acute thoracolumbar spinal injuries were assessed. We defined the epiconus as the region from the terminal end of the spinal cord to the proximal 1.0 to 2.25 vertebral bodies, the conus medullaris as the region proximal to < 1.0 vertebral bodies, and the cauda equina as the distal part of the nerve roots originating from the spinal cord. On the basis of the distance from the terminal end of the spinal cord to the narrowest level of the spinal canal, the narrowest levels were ordered as follows: the epiconus followed by the conus medullaris and cauda equina. The narrowest levels were the epiconus in 22 patients, conus medullaris in 37 patients, and cauda equina in 25 patients. On admission, significantly more patients had a narrowed epiconus of Frankel grades A-C than a narrowed cauda equina. At the final follow-up, there were no significant differences in neurological recovery among those with epiconus, conus medullaris, or cauda equina syndrome. Anatomically classifying the narrowest lesion is useful for clarifying the differences and similarities among these three syndromes.

Prevalence of global spinal malalignment and the influence on LBP and HR-QOL in a healthy, nonelderly population. A cross sectional analysis, including bone mineral density, skeletal muscle mass index, and back muscle extensor strength.

Background: In healthy, nonelderly populations, prevalence of 3 modifiers of global spinal malalignment (GS-MalAlign) (PT ≧20°, PI-LL≧10°, SVA≧40 mm) remains unknown. The clinical significance has not been determined. The purposes are to disclose the prevalence of the 3 modifiers of GS-MalAlign, and evaluate the influence on LBP, and HR-QOL related to bone mineral density (BMD), skeletal muscle mass index (SMI), and back muscle extensors strength (BMES) in a healthy, nonelderly population. Methods: A mono-centric, cross-sectional survey. Three hundred and 2 participants (18< age <65 years) without ADL disturbance were consecutively enrolled. Sagittal parameters of the spine and the pelvis were measure on whole spine radiograms. BMD and SMI were determined using DEXA. BMES was defined as a maximum extension force at the T4 to T7 level and measured by a strain-gauge dynamotor. LBP was checked through interview. HR-QOL was ascertained by score of Medical Outcome Study Short-Form 36-Health Survey (SF-36v2). Results: The final analysis could be done in 84 females and 179 males. PT≧20°, PI-LL≧10°, and SVA≧40 mm were found in 12% (31/263), 11% (31/263), and 6% (16/263), and each mean value was 25.0 ± 4.0°, 15.3 ± 5.9°, and 52.7 ± 12.2 mm (Mean ± S.D.). Prevalence of LBP was significantly higher in the participants with PI-LL≧10° than with PI-LL<10°; 43% (12/28) versus 21% (49/235) (p<.05). PI-LL≧10° only had an association with LBP (OR: 3.0435, 95% CI, 1.1378-8.141, p<.05). Four 2% of participants (4/263) associated with all 3 modifiers had LBP and a significantly lower mental component summary score of SF-36v2 (p<.05). Conclusions: Some of individuals are associated with GS-MalAlign even in healthy, nonelderly populations. There is a possibility that PI-LL ≧10° results in LBP within a degree of no ADL disturbance, and it is speculated that coexistence of all 3 modifiers of GS-MalAlign would lead to a poor mental HR-QOL.

Long-term effect of immobilization in external rotation after first-time shoulder dislocation: an average 18-year follow-up.

BACKGROUND: Immobilization in external rotation (ER) after a first-time shoulder dislocation was introduced to reduce the risk of recurrence compared with immobilization in internal rotation (IR), but its efficacy remains controversial. The purpose of this study was to determine the long-term effect of immobilization in ER after a first-time shoulder dislocation. METHODS: Between October 2000 and March 2004, 198 patients with a first-time anterior dislocation of the shoulder (average age 37) were randomly assigned to immobilization in ER (ER group = 104 shoulders) or IR (IR group = 94 shoulders) for 3 weeks. At an average 2-year follow-up, 159 patients (80.3%) were available for evaluation. In the current study, these 159 patients were further followed up and interviewed by telephone. The following items were evaluated: recurrent instability, apprehensive feeling, surgical intervention, limitation in the range of motion, return to sports, and the Single Assessment Numeric Evaluation (SANE) score. RESULTS: The average follow-up period was 18.2 years (range, 16-20 years). Fifty-six patients were available for follow-up with the follow-up rate of 35%. The number of recurrent patients was 6 of 27 (22%) in the ER group and 6 of 29 (21%) in the IR group (P = .889). The number of surgically stabilized patients was 3 of 27 (11%) in the ER group and 10 of 29 (34%) in the IR group (P = .038). In total, the recurrence rate was 33% (9 of 27) in the ER group and 55% (16 of 29) in the IR group (P = .100). Adding the surgical cases and those with the SANE score ≤70% as failure cases, the failure rate in the ER group (26%) was significantly lower than that in the IR group (52%) (P = .048). Among those who survived without surgical intervention, there were no significant differences in apprehensive feeling, return to sports, limited range of motion, and the SANE score between the groups. CONCLUSIONS: Immobilization in ER reduced the risk of surgical intervention compared with IR in the long term.

Histological demonstration of the gas precursor in a symptomatic L5-S1 disc herniation containing gas: A case report.

Vacuum phenomenon is a commonly observed radiological entity in the degenerated intervertebral discs of the lumbar spine in the elderly population. The entity is frequently asymptomatic. Although disc herniation containing gas (DH-CoG) is commonly associated with the vacuum phenomenon, DH-CoG associated with clinical symptoms is a rare condition. There are very few reports which have histologically demonstrated the existence of the gas itself within DH-CoG. Herein, we report a rare case of a 65-year-old female with symptomatic DH-CoG at L5/S1. The patient was admitted to our hospital with a one-month history of pain in the left buttock and leg in addition to neurogenic claudication. Roentgenograms illustrated a degenerative lumbar spine with the vacuum phenomenon at the L5/S1 disc space. Computed tomography showed a round and low-density lesion within the spinal canal at left L5/S1. Additionally, a lesion characterized by an iso- and partially hypointense signal on T1 and hypointense signal on T2 was detected in magnetic resonance imaging (MRI) by the spin-echo method. The decision for posterior lumbar interbody fusion surgery using pedicle screws was made as the symptoms had not responded to the conservative treatment. After a degenerated prolapsed nucleus was carefully extracted, the specimen was sent to the laboratory for histopathological analysis. The prolapsed nucleus of DH-CoG histologically showed many small vacuoles containing degenerated mucopolysaccharides. The left leg pain drastically resolved on the first post-operative day, and no recurrence had been observed. Degenerated mucopolysaccharide may be a precursor of nitrogen or "the gas itself" in DH-CoG. Surgical intervention for DH-CoG should be considered if conservative treatment fails.

Comparison of Posterior Lumbar Interbody Fusion and Microendoscopic Muscle-preserving Interlaminar Decompression for Degenerative Lumbar Spondylolisthesis With >5-Year Follow-up.

STUDY DESIGN: Retrospective analysis of prospectively collected observational multicenter data. OBJECTIVE: To compare the clinical results and rates of revision surgery after posterior lumbar interbody fusion (PLIF) and microendoscopic muscle-preserving interlaminar decompression (ME-MILD) in patients with single-level, mild degenerative lumbar spondylolisthesis (DLS) and follow-up of at least 5 years. SUMMARY OF BACKGROUND DATA: Surgery for symptomatic DLS remains controversial. Evaluating long-term results may reveal problems such as adjacent segmental diseases of the PLIF and decreased quality of life because of slippage and restenosis of the ME-MILD. METHODS: We enrolled 116 patients who underwent PLIF (79 patients) or ME-MILD (37 patients). Operative times, blood losses, surgical complications, Short-Form 36 (SF-36), Japanese Orthopedic Association (JOA) score, the JOA Back Pain Questionnaire (JOABPEQ), visual analog scales (VAS), and Zurich Claudication Questionnaire (ZCQ) were evaluated. RESULTS: PLIF was observed to require significantly longer operative times and entailed greater operative blood losses than did ME-MILD (151.1 vs. 119.9 min; 202.2 vs. 6.4 mL, respectively). Surgery-related complications were identified in 3 cases in the PLIF group and 2 cases in the ME-MILD group. Seventy-eight patients (50 and 28 patients in the PLIF and ME-MILD groups, respectively) were successfully followed-up for >5 years. The follow-up rate was 67.2%. No significant differences between the groups were found in terms of preoperative and postoperative JOA scores, postoperative JOABPEQ, VAS, or ZCQ. Significant improvements in JOA scores were observed in both groups. Significant improvements in the SF-36 were observed in all subscales except in role physical, general health, vitality, and mental health in the ME-MILD group. Revision surgical procedures were performed in 2 patients in the ME-MILD group and 4 patients in the PLIF group. CONCLUSIONS: PLIF and ME-MILD resulted in equivalent improvements in SF-36 and JOA scores. There were no differences in revision surgery rates among patients with single-level, mild DLS. LEVEL OF EVIDENCE: Level III-a retrospective analysis.

Limaprost or Pregabalin: Preoperative and Postoperative Medication for Pain due to Lumbar Spinal Stenosis.

PURPOSE: We aimed to evaluate the incidence of (and risk factors for) postoperative pregabalin and/or limaprost to treat persistent numbness and/or pain of the lower extremities after lumbar spinal stenosis (LSS) surgery. METHODS: Medical records of 329 patients (168 men, 161 women; average age 70 years) were retrospectively reviewed for data on the duration of LSS diagnosis; LSS disease; preoperative medication (limaprost, pregabalin, or combined limaprost/pregabalin; duration); symptoms; preoperative/postoperative intermittent claudication (IC); operation type; and postoperative medication and period. RESULTS: Limaprost, pregabalin, and combined limaprost/pregabalin were prescribed preoperatively for 43%, 7%, and 5% of patients, respectively. At an average of 21 months postoperatively, limaprost, pregabalin, and combined therapy were prescribed in 11%, 8%, 4% of patients, respectively. Medication requirement was significantly lower postoperatively than preoperatively (P < 0.0001). Significant risk factors for required postoperative medication were required preoperative medication (odds ratio [OR] 3.088, 95% confidence interval [CI] 1.679 to 5.681]; postoperative period (OR 1.063, 95% CI 1.031 to 1.096); and postoperative IC (OR 3.868, 95% CI 1.481 to 10.103). A negative impact from postoperative medication was seen in patients who had undergone decompression surgery (OR 0.589, 95% CI 0.377 to 0.918). CONCLUSIONS: Overall, 23% of LSS patients required medication for pain and/or numbness at 21 months postoperatively. Significant factors portending required postoperative medication were preoperative medication, longer postoperative period, and postoperative IC. A negative influence from postoperative medication was seen in patients who had undergone decompression surgery without fusion.

ACDF with a PEEK cage clinically provides a good outcome with minor donor site morbidity despite unsatisfactory radiological findings-A prospective cohort study of a PEEK cage in stand-alone usage.

STUDY DESIGN: A prospective cohort study was conducted on patients with anterior cervical decompression and fusion (ACDF) with a polyetheretherketone cage (PEEKc). BACKGROUND: Advantages of a PEEKc have been proposed in the study. However, benefits of using a PEEKc in ACDF are still controversial. OBJECTIVE: To investigate the advantages of a PEEKc in ACDF. MATERIALS AND METHODS: A total of 27 patients was enrolled in the study. The mean age of patients was 55±10 years (mean±standard deviation). The mean duration of symptoms was 17±21 months. Surgery was conducted at C3/4 in 1, C4/5 in 3, C5/6 in 11, C6/7 in 9, C7/T1 in 2, and C5/6/7 in 1 patient. The mean follow-up period was 2.1±1.3 years. Clinical outcomes were analyzed by the Japanese Orthopedic Association Scores (JOA scores) and its recovery rate. Perioperative complications were also investigated. Radiologically, studies were conducted on interbody lordotic angle (IBLA), interbody height (IBH), and bone fusion rates. RESULTS: The JOA score was 14.7±1.4 preoperatively and 16.3±1.3 at the final follow-up. A significant improvement was observed (p<0.05). The mean recovery rate of JOA scores was 74.0±25.0%. The preoperative IBLA was 0.5±6.1°. The mean IBLA at the final follow-up was 1.9±5.6°. The preoperative IBH was 34.2±3.5 mm. The mean IBH at the final follow-up was 34.3±3.5 mm. No significant improvement in IBLA and IBH was observed. A complete union rate at 1 year and 2.3 years (range, 2.0-6.0) after surgery was 29% (8/28 segments) and 61% (11/18 segments). No major complications were observed. CONCLUSIONS: Despite an unsatisfactory bone union rate and no significant improvement in IBLA and IBH at the final follow-up, ACDF with a PEEKc clinically provided a stable outcome with less surgical invasion and minor donor-site morbidity.

Clinical diagnosis of upper lumbar disc herniation: Pain and/or numbness distribution are more useful for appropriate level diagnosis.

OBJECTIVE: The purpose of this study is to disclose the characteristic symptoms and signs in L2, L3 and L4 nerve root disturbance. MATERIALS AND METHODS: Fifty eight patients who underwent lateral herniotomy were analyzed. Breakdowns are 15 patients with L2/3 lateral disc herniation (group A), 20 patients with L3/4 lateral disc herniation (group B), and 23 patients with L4/5 lateral disc herniation (group C). The following items were examined: 1) localization of the subjective pain and numbness, 2) objective neurological findings, including deep tendon reflex, manual muscle strength (MMT), straight leg raising test (SLRT) and femoral nerve stretch test (FNST). RESULTS: In group A, subjective pain and/or numbness was present in the thigh aspect, proximal to the knee joint in all patients. In group B, 80% of the patients had subjective pain and/or numbness in the medial site of the knee joint. In group C, the subjective pain and/or numbness was localized in various aspects of the lower extremity. Weakness in the iliopsoas, the femoral quadriceps, and the anterior tibial muscle were observed in 60-95%, 27-70%, 0-43% of three groups, respectively. Depression or absence of the patella tendon reflex was present in 27-100% of three groups. SLRT and FNST were positive in 13-87% and 91-95% of three groups. CONCLUSION: Symptomatic levels of nerve root disturbance in the upper lumbar spine could not be accurately identified by objective neurological findings alone. Pain and/or numbness localized in the thigh area proximal to the knee joint is a specific sign of L2 nerve root disturbance. Either subjective pain or numbness in the medial knee joint aspect is another key sign which strongly suggests L3 nerve root disturbance.

Spine-shortening vertebral osteotomy for tethered cord syndrome: report of three cases.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To review findings from 3 patients who underwent spine-shortening vertebral osteotomy for tethered cord syndrome with a minimum follow-up of 3 years. SUMMARY OF BACKGROUND DATA: Surgical detethering is the gold standard for symptomatic tethered cord syndrome. However, complications such as cerebrospinal fluid leakage and neurologic deterioration are common. Spine-shortening vertebral osteotomy, proposed by Kokubun, is an alternative surgical technique to reduce neural tension indirectly. However, case series of this novel procedure for tethered cord syndrome have not been reported in the English literature. METHODS: Three patients aged 13, 22, and 27 years presented with progressive pain and/or neurologic dysfunction. They underwent spine-shortening vertebral osteotomy of L1 with a pedicle screw and rod system. Their clinical and radiologic outcomes are reviewed. RESULTS: All patients got relief from their preoperative symptoms after surgery, and no complications occurred. Complete bone union was obtained in all patients without correction loss. CONCLUSION: Spine-shortening vertebral osteotomy can be a safe and alternative surgical technique for tethered cord syndrome.

Immobilization in external rotation after shoulder dislocation reduces the risk of recurrence. A randomized controlled trial.

BACKGROUND: An initial anterior dislocation of the shoulder becomes recurrent in 66% to 94% of young patients after immobilization of the shoulder in internal rotation. Magnetic resonance imaging and studies of cadavera have shown that coaptation of the Bankart lesion is better with the arm in external rotation than it is with the arm in internal rotation. Our aim was to determine the benefit of immobilization in external rotation in a randomized controlled trial. METHODS: One hundred and ninety-eight patients with an initial anterior dislocation of the shoulder were randomly assigned to be treated with immobilization in either internal rotation (ninety-four shoulders) or external rotation (104 shoulders) for three weeks. The primary outcome measure was a recurrent dislocation or subluxation. The minimum follow-up period was two years. RESULTS: The follow-up rate was seventy-four (79%) of ninety-four in the internal rotation group and eighty-five (82%) of 104 in the external rotation group. The compliance rate was thirty-nine (53%) of seventy-four in the internal rotation group and sixty-one (72%) of eighty-five in the external rotation group (p = 0.013). The intention-to-treat analysis revealed that the recurrence rate in the external rotation group (twenty-two of eighty-five; 26%) was significantly lower than that in the internal rotation group (thirty-one of seventy-four; 42%) (p = 0.033) with a relative risk reduction of 38.2%. In the subgroup of patients who were thirty years of age or younger, the relative risk reduction was 46.1%. CONCLUSIONS: Immobilization in external rotation after an initial shoulder dislocation reduces the risk of recurrence compared with that associated with the conventional method of immobilization in internal rotation. This treatment method appears to be particularly beneficial for patients who are thirty years of age or younger.

PLIF with a titanium cage and excised facet joint bone for degenerative spondylolisthesis--in augmentation with a pedicle screw.

OBJECTIVES: To determine the validity of posterior lumbar interbody fusion (PLIF) using a titanium cage filled with excised facet joint bone and a pedicle screw for degenerative spondylolisthesis. METHODS: PLIF using a titanium cage filled with excised facet joint bone and a pedicle screw was performed in 28 consecutive patients (men 10, women 18). The mean age of the patients was 60 years (range, 52 to 75 y) at the time of surgery. The mean follow-up period was 2.3 years (range, 2.0 to 4.5 y). The operation was done at L3/4 in 5, L4/5 in 20, and L3/4/5 in 3 patients. The mean operative bleeding was 318+/-151 g (mean+/-standard deviation), and the mean operative time was 3.34+/-0.57 hours per fixed segment. Clinical outcome was assessed by Denis' Pain and Work scale. Radiologic assessment was done using Boxell's method. Fusion outcome was assessed using an established criteria. RESULTS: On Pain scale, 20 and 8 patients were rated P4 and P5 before surgery, and 11, 12, 2, 2, and 1 patients were rated P1, P2, P3, P4, and P5 at final follow-up, respectively. On Work scale (for only physical labors), 12 and 9 patients were rated W4 and W5, before surgery, and 12, 5, 1, and 3 patients were rated W1, W2, W3 and W5 at final follow-up, respectively. There was significant difference in clinical outcome (P<0.01, Wilcoxon singled-rank test) The mean %Slip and Slip Angle was 17.9+/-8.1% and 3.9+/-5.8 degrees before surgery. The mean % Slip and Slip Angle was 5.4+/-4.4% and -2.0+/-4.8 degrees at final follow-up. There was a significant difference between the values (P<0.01, paired t test). "Union" and "probable union" was determined in 29 (93.5%) and 2 (6.5%) of 31 operated segments at 2.3 years (range, 2.0 to 4.5 y), postoperatively. CONCLUSIONS: PLIF using a titanium cage filled with excised facet joint bone and a pedicle screw provided a satisfactory clinical outcome and an excellent union rate without harvesting and grafting the autologous iliac bone.

A new method of immobilization after traumatic anterior dislocation of the shoulder: a preliminary study.

This preliminary prospective study was conducted to determine whether immobilization with the arm in external rotation would decrease the rate of recurrence after initial traumatic anterior dislocation of the shoulder. Forty patients with initial shoulder dislocations were assigned to (1) conventional immobilization in internal rotation (IR group, n = 20) or (2) a new method of immobilization in external rotation (ER group, n = 20). The recurrence rate was 30% in the IR group and 0% in the ER group at a mean 15.5 months. The difference in recurrence rate was even greater among those who were aged less than 30 years (45% in the IR group and 0% in the ER group). Immobilization with the arm in external rotation is effective in reducing the rate of recurrence after initial dislocation of the shoulder.

Dynamic stabilizing function of the deltoid muscle in shoulders with anterior instability.

BACKGROUND: The stabilizing role of the deltoid muscle has not been extensively studied. PURPOSE: To study the contribution of the deltoid muscle to anterior stability of the shoulder. STUDY DESIGN: Controlled laboratory study. METHODS: We used nine fresh cadaveric shoulders with the arm at 90 degrees of abduction and 90 degrees of external rotation. The position of the humeral head was monitored by an electromagnetic tracking device with 0 and 1.5 kg of anterior translation force; with 0, 1, 3, and 5 kg of force applied to each of the anterior, middle, and posterior portions of the deltoid muscle; and with the capsule intact, vented, and with a simulated Bankart lesion. RESULTS: With the capsule intact, anterior displacement was significantly reduced by application of load to the middle deltoid muscle. After the capsule was vented, load application to the anterior, middle, or posterior deltoid muscle significantly reduced anterior displacement. With a simulated Bankart lesion, effects of muscle loading were most apparent: anterior displacement was significantly reduced with loading of each muscle portion. CONCLUSION: The deltoid muscle is an anterior stabilizer of the glenohumeral joint with the arm in abduction and external rotation. CLINICAL RELEVANCE: The stabilizing function of the deltoid muscle takes on more importance as the shoulder becomes unstable.

Glenoid osteophyte and rotator cuff tears: an anatomic study.

The purpose of this study was to determine the morphologic characteristics of the glenoid osteophyte and its relationship to rotator cuff tears. Eighty-six cadaveric shoulders were studied. After inspection of cuff pathology, the glenoid was examined with soft x-rays. Histologically, degenerative changes of the articular cartilage and the labrum were assessed. There were 30 shoulders with rotator cuff tears (35%). Two types of glenoid osteophyte were identified: angular and hooked. Both osteophytes were commonly observed in the anterior to inferior portions of the glenoid. The length of hooked osteophytes was significantly greater in shoulders with full-thickness tears (2.7 +/- 2.2 mm [mean plus minus SD]) than in those with other cuff conditions (P =.0058). The hooked osteophyte was more commonly observed in shoulders with full-thickness tears (43%) and associated with degenerative changes of the cartilage and labrum. We conclude that the hooked osteophyte of the glenoid is characteristic in shoulders with full-thickness tears of the rotator cuff.