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Published 10/1/2018

Second Look - Clinical

Hip and knee

Overnight stay after THA—Same-day discharge (SDD) following total hip arthroplasty (THA) could be related to personal patient preference, according to a prospective cohort study published in The Journal of Arthroplasty (online). The study included 106 patients younger than 75 years who did not need to use a walker, had an American Society of Anesthesiologists score of 1–3, had a body mass index < 40 kg/m2, and agreed to SDD prior to surgery. Seventy-four percent of SDD-eligible candidates were discharged on schedule (n = 78), whereas the remaining 26 percent (n = 28) were not, due to patient preference (n = 12), dizziness/hypertension (n = 8), failure to clear physical therapy (n = 5), urinary retention (n = 2), and pain management (n = 1). Those who did not leave the same day as their surgery were also more likely to report multiple allergies, anxiety/depression, obstructive sleep apnea, and rheumatoid arthritis.

Knee arthrodesis after failed TKA—A retrospective cohort study published in the Archives of Orthopaedic and Trauma Surgery (online) found that knee arthrodesis may be an alternative to revision surgery for patients with failed, infected total knee arthroplasty (TKA).

Researchers gathered data for 81 patients with periprosthetic joint infection of the knee who were treated between 2008 and 2014. Thirty-six patients were treated with a modular intramedullary arthrodesis nail, and 45 received two-stage revision TKA. The arthrodesis group had higher infection-free rates (n = 32, 88.9 percent) than the revision TKA group (n = 36, 80.0 percent). Oxford Knee Scores were slightly higher for arthrodesis patients (38.7) than revision TKA patients (36.5). Mean visual analog scale (VAS) pain scores were similar between both groups (arthrodesis = 3.2; revision TKA = 3.1). Revision rates were lower among arthrodesis patients (1.2) than revision TKA patients (2.8). Researchers concluded that arthrodesis may be a good option for certain patients when other options have been exhausted.

Limited knee function after ACL surgery—A long-term cohort study published in The American Journal of Sports Medicine (online) concluded that some risk factors for inferior knee function after anterior cruciate ligament (ACL) reconstruction may be modifiable. Researchers used prospectively collected data from the Swedish National Knee Ligament Register to identify 874 patients who had undergone ACL reconstruction between January 2005 and December 2006. Patient- and surgery-related risk factors were assessed with patients’ mean Knee Injury and Osteoarthritis Outcome Score (KOOS) across four subscales: pain, knee-related symptoms, function in sport and recreation, and knee-related quality-of-life (KOOS4). Patients who reported a higher preoperative KOOS pain score were more likely to have higher scores on the pain, symptoms, and sport subscales and the KOOS4. A higher preoperative BMI was also a predictor of lower scores on the three KOOS subscales and the KOOS4. None of the predictors was significant across all four subscales.

OA therapy and knee replacement—A nested, case-control study published in Arthritis Research & Therapy (online) did not find a link between common oral therapies for osteoarthritis (OA) and the occurrence of knee replacement (KR). Using the Osteoarthritis Initiative database, researchers studied 218 patients who had a KR and matched them to 540 controls. They assessed use of oral OA therapies (including acetaminophen, nonsteroidal anti-inflammatory drugs, cyclooxygenase-2 inhibitors, narcotics, and glucosamine/chondroitin sulfate) three years before KR and did not find a significant association between KR and exposure to the OA therapies. KR was significantly more common in Caucasian participants, as well as those with a BMI ≥ 27 kg/m2. Researchers concluded that the greatest risk factors for KR were disease severity, symptoms, and high BMI.

XPLE hip implants—An observational study published in The Journal of Bone & Joint Surgery (JBJS; online) found that the likelihood for revision surgery following THA may be reduced when cross-linked polyethylene (XPLE) implants are used compared to conventional noncross-linked polyethylene (CPE) implants. Researchers analyzed 240,302 THAs (CPE = 41,171; XPLE = 199,131) performed to treat OA between 1999 and 2016. The 16-year cumulative percentage of primary THA revisions was 11.7 percent in the CPE group and 6.2 percent in the XPLE group. The researchers said that the improved longevity in THA means younger patients may be able to undergo the surgery with reduced risk of revision surgery in the future.

ACL failure rates—A retrospective study published in the Journal of Pediatric Orthopaedics (August) found that success rates for ACL reconstruction surgery may depend on age, graft selection, and surgical technique. Researchers studied 561 pediatric patients (age range, 5–19 years) who had undergone primary ACL reconstruction surgery between 2002 and 2013. The total failure rate was 9.6 percent (n = 54), and the average time to failure was approximately 13.6 months. The type of graft used was the greatest indicator for failure. Soft-tissue grafts and patellar tendon grafts failed at a 13 percent and 6 percent rate, respectively. Maturity (growth plate status) and surgical technique also affected failure rates. Hamstring grafts and anatomic femoral tunnels appeared to fail earlier. Approximately 8 percent of patients sustained a contralateral ACL injury.

Kinematically aligned TKA—A study published in The Journal of Arthroplasty (online) found that kinematically aligned (KA) TKA using patient-specific instrumentation (PSI) did not impact 10-year implant survival. Researchers retrospectively assessed 222 knees in 217 patients treated in 2007 with primary TKA. All patients were treated with KA TKA using PSI without restricting the degree of preoperative deformity and with the restoration of the native joint lines and limb alignment. The implant survivorship rate was 97.5 percent for revision for any reason and 98.4 percent for aseptic failure. The average 10-year Oxford Knee Score and Western Ontario & McMaster Universities Osteoarthritis Index scores were 43 and seven, respectively.

OA progression in hip arthroscopy—In a long-term follow-up study published in Archives of Orthopaedic and Trauma Surgery (online), researchers assessed clinical and radiologic outcomes in 43 patients who had undergone hip arthroscopy between 1998 and 2006. Primary endpoints were subsequent THA or other hip surgery; secondary endpoints were OA progression and patient-reported outcome measures (PROMs). Overall, 20 patients had undergone subsequent surgery, 11 of whom required THA. No significant progression of OA was found in patients who did not undergo THA. Seventy-seven percent of patients (n = 33) said they would undergo hip arthroscopy again in the same situation. The Forgotten Joint Score-12 was the only PROM that differed in patients who had revision surgery and those who did not.

Delaying fractured hip surgery—A population-based, propensity-matched cohort study published in JBJS (Aug. 15) found that delaying hip fracture surgery for more than 24 hours after arrival at the emergency department increased medical costs and hospital length of stay. Data were collected for 42,230 patients who had undergone hip fracture surgery performed by 522 different surgeons at 72 hospitals in Ontario, Canada, between 2009 and 2014. The mean cost for patients was $39,497. Among those who did not receive immediate surgery, one-year medical costs were $2,638 higher, on average, and patients spent an average 0.610 days longer in the hospital, compared to patients who had undergone surgery within 24 hours. Researchers said this information may provide a financial incentive to mitigate delays in hip fracture surgery.

Shoulder and elbow

Video games and athletes—Young baseball players may be negatively affected by playing video games for an extended period of time, according to a study published in the Journal of Shoulder and Elbow Surgery (online). The study assessed 200 young baseball players aged 9–12 years who participated in the National Junior Sports Clubs Baseball Festival in 2017. Prolonged periods of playing video games led to elbow or shoulder pain in 30 percent of participants. Researchers found that those who played video games for more than three hours per day were at significantly greater odds of having shoulder or elbow pain compared to those who played for one hour or less each day.

Strength level after shoulder injury—A single-experiment study published in BMC Musculoskeletal Disorders (online) found that age- and sex-related differences in strength may be more predictive of shoulder injuries than muscle fatigue resistance. Researchers measured muscle fatigability in 40 participants (20 males, 20 females) based on upper trapezius muscle fiber conduction velocity (CV) and relative maximum strength at three levels of shoulder abduction. Both male and female groups had 10 young (mean age, 26 years) and 10 older (mean age, 59.6 years) participants. Upper trapezius CV differed based on age and sex, with the older and female groups having greater levels of muscle fatigue resistance. Shoulder abduction endurance time varied significantly between age groups; the young and male groups exhibited greater levels of strength. Because work-related musculoskeletal disorders more commonly affect older and female populations, the researchers noted that muscle fatigability is not likely a contributor.

Predictors of pain after rotator cuff repair—Psychosocial factors may be more indicative of pain than structural factors following arthroscopic rotator cuff repair, according to a prospective study published in the Journal of Shoulder & Elbow Surgery (online). Researchers gathered data on 93 patients (mean age, 56 years; 54 percent male) who were evenly categorized by tear size; 68 percent of tears were traumatic. They analyzed pre- and postoperative VAS pain scores, narcotic usage, range of motion (ROM), and functional and psychological assessments via the American Shoulder and Elbow Surgeons (ASES) Standardized Shoulder Assessment Form, Simple Shoulder Test, Western Ontario Rotator Cuff Index (WORC), and RAND 36-item Short Form Survey questionnaires. At one-year follow-up, ROM, VAS, ASES, and WORC scores had improved greatly. Preoperative narcotic use, high VAS scores prior to the procedure, and lower WORC index and emotion scores were associated with higher pain scores at one-year follow-up.

Bone health

OA and levels of adiponectin—A meta-analysis published in the journal Lipids in Health and Disease (online) found that levels of adiponectin were higher in patients who had OA compared to those who did not. Researchers used data from 10 articles detailing 13 case-control studies that included 1,255 patients. Results indicated stronger evidence of high adiponectin levels among patients with OA of the knee than those with OA in the hand or hip. Data were divided to differentiate between white and Asian patients, and the study identified adiponectin as a biomarker in both cohorts.

Lateral versus medial UKA—A study published online in The Journal of Arthroplasty (online) found that OA may advance more quickly in patients undergoing lateral unicompartmental knee arthroplasty (UKA) compared to medial UKA. Researchers graded preoperative and one- and five-year postoperative radiographs for OA in 20 lateral and 114 medial UKA patients in the unoperated tibiofemoral (TF) and patellofemoral (PF) compartments using the Kellgren (0–4-point global scale for OA), Ahlbäck (0–5-point scale based on joint space narrowing), and Altman (0–12-point composite criteria score) scales. All mean disease grades for the TF and PF compartments worsened over time. Kellgren grade changes occurred faster five years following surgery in lateral patients in the TF and PF compartments, and Ahlbäck grades increased faster in the TF compartment. After the researchers adjusted for confounding factors, the Kellgren grade increased for the TF compartment in lateral and medial patients by 1.1 and 0.6 points, respectively.

Osteoporosis drugs and facture risk, costs—A study published in Osteoporosis International (online) observed a correlation between continuous use of osteoporosis medication and a decreased risk of fracture in older women. The study included 294,369 female Medicare beneficiaries 66 years of age or older who were diagnosed with and began taking osteoporosis medication between Jan. 1, 2009, and June 30, 2011. Of the patients, 32.9 percent were persistent users of their medication (no gap ≥ 60 days for one year or longer) and 67.1 percent were nonpersistent users (< 12 months continuous use). Among the persistent group, fracture incidence rates were 16.2 per 100 patient-years before initiation (1–6 months before initiating medication) and 4.1 after initiation (up to 18 months after initiating medication). For the nonpersistent group, rates were 19 and 7.3 per 100 patient-years before and after initiation, respectively. Total average patient health costs for nonpersistent users were $19,181 per year compared to $14,476 for persistent users. The researchers said payers and patients would benefit from interventions aimed at improving medication persistence.

Bone union rates after tibial osteotomy—Patients who underwent opening wedge high tibial osteotomy (OWHTO) with no bone graft (NBG) showed better incorporation rates at different periods of follow-up compared to those with synthetic bone graft (SBG), according to a study published in the journal Arthroscopy (online). The retrospective study assessed OWHTOs performed in 71 knees between 2012 and 2015, including those performed with SBG (n = 33) and those without (n = 38). The NBG group showed much greater union rates after six months, one year, and two years. At two years, 100 percent of NBG patients and 93.9 percent of SBG patients displayed incorporation in union zone three.

Fracture after gastric bypass—A retrospective cohort study published in the Journal of Bone and Mineral Research (online) revealed that patients who had undergone gastric bypass had an increased risk of fall injury and fracture after surgery. Researchers assessed Swedish national databases to identify 38,971 obese patients who had undergone the surgery, 7,758 of whom were diabetic. Gastric bypass was associated with an approximately 30 percent increased risk of fractures in patients with diabetes (32 percent) and without diabetes (26 percent). Flexible parameter models showed that risk elevated over time. The operation also increased the risk of fall injury without fracture. Researchers found no correlation between degree of weight loss or calcium and vitamin D supplementation.

Hand and wrist

RIAP for RA-damaged wrist—Resection interposition arthroplasty (RIAP) may be a good alternative for severe wrist damage resulting from RA, according to a retrospective study published in BMC Musculoskeletal Disorders (online). Researchers assessed data from 34 wrists (28 patients) between 1989 and 2002, with a mean follow-up of 9.3 years. A modified, 100-point version of Clayton’s scoring system and a functional questionnaire were used to determine patients’ results. They observed the following Clayton scores: 29.4 percent of wrists (n = 10) were excellent (90–100 points), 41.2 percent (n = 14) were good (70–89 points), 11.8 percent (n = 4) were fair (60–69 points), and 17.6 percent (n = 6) were poor (< 60 points). Seventy-one percent of patients reported satisfaction with subsequent pain levels, function, and daily activities. Patients more likely to report positive outcomes included those who were younger, had the surgery earlier, did not have long-term disease, and had lesser involvement of other joints.


Thoracic disk and SAC—A retrospective study published in The Spine Journal (July) measured kinematic changes of the intervertebral disk and space available for the spinal cord (SAC) of the thoracic spine. The study included 105 patients who had undergone kinematic MRI of the thoracic spine. Researchers found kinematic changes from flexion to extension in the thoracic disks and SAC from T4–T5 to T11–T12. The thoracic intervertebral disk area’s mean value was larger in flexion than extension in those areas. Prominent disk bulging was found at T8–T9 between flexion and extension, T9–T10 between neutral and flexion, and T9–T10 between flexion and extension. Researchers concluded that for patients with thoracic myelopathy, one etiology for neurogenic deterioration may be kyphotic deformities.

OPLL after laminoplasty—A retrospective case series published in The Spine Journal (July) found that disk type and ROM may be predictive of ossification of the posterior longitudinal ligament (OPLL) progression following laminoplasty. Researchers included data on 34 patients (86 segments) with cervical myelopathy secondary to OPLL. Ossified masses were categorized based on disk space involvement: type 1 (no involvement), type 2 (involving disk space but not crossing), type 3 (crossing disk space but not fused), and type 4 (complete bridging). Severe progression (change in thickness > 2 mm) occurred most often in types 2 (n = 8/29) and 3 (n = 7/16) and was significantly less common in types 1 (n = 1/35) and 4 (n = 0/6). ROM > 5 degrees was associated with severe progression in types 2 and 3 (52 percent versus 8 percent, respectively). Mean OPLL progression was 0.5 mm, 1.3 mm, and 1.5 mm in types 1, 2, and 3, respectively.

Prescribing considerations

Leftover opioid medication counseling—Most older adults with an opioid prescription do not have conversations with their healthcare providers about what to do with leftover pills, according to a report from the National Poll on Healthy Aging at the University of Michigan. Researchers surveyed 589 American adults 50–80 years old who had received an opioid prescription in the past two years. They found that only 37 percent had had a discussion with their providers about what to do with any leftover medications. Half of the adults reported having leftover medications, and 86 percent said they hold onto pills for use in case of future pain. Just 13 percent said they returned extra medications to an approved location. Researchers noted that keeping extra opioids in the home is the most common way for family members or others to misuse such medications.