Tomislav Smoljanović

Traumatic and Overuse Injuries Among International Elite Junior Rowers

Background Junior rowers have competed internationally for over 4 decades, and there are no epidemiological data available on traumatic and overuse injury in this population. Objective To define the types of musculoskeletal problems present in international elite-level junior rowers and to determine whether gender, physical stature, rowing discipline, and training programs affect the incidence of reported injuries. Study Design Descriptive epidemiology study. Methods Injury data were obtained from a total of 398 rowers (42% female, 58% male) who completed a 4-page questionnaire on injury incidence while participating at the Junior World Rowing Championships in Beijing, People’s Republic of China, in August 2007. Results Overall, 290 (73.8%) reported injuries involved overuse, and 103 (26.2%) were related to a single traumatic event. Female rowers were injured more frequently than male rowers (110.2 vs 90.5 injuries per 100 rowers). In both genders, the most common injury site was the low back followed by the knee and the forearm/wrist. The severity of reported injuries was incidental in 65.1%, minor in 21.4%, moderate in 10.4%, and major in 3.1% of cases. The rowers with traumatic injuries had less rowing experience than the uninjured rowers (median [C] ± interquartile range [Q] = 3 ± 3 years vs 4 ± 3 years; P = .043, Mann-Whitney test). Sweep rowers who changed rowing side during the current season had significantly more acute-onset low back injuries (P = .012, χ2 test) than those who did not change rowing side during the same period. The incidence of traumatic injuries was significantly lower in rowers who regularly performed more than 10 minutes of posttraining stretching (P = .030, χ2 test). Athletes who ran more than once a week had more overuse knee injuries than those who ran once or less per week (P = .033, χ2 test). Conclusion Elite junior rowers attending the World Rowing Championships reported predominantly overuse injuries of low severity during the current rowing season. Low back injuries were the most frequent complaint of elite-level junior rowers.

Bone morphogenetic protein (BMP)1-3 enhances bone repair

Members of the astacin family of metalloproteinases such as human bone morphogenetic protein 1 (BMP-1) regulate morphogenesis by processing precursors to mature functional extracellular matrix (ECM) proteins and several growth factors including TGFβ, BMP2, BMP4 and GFD8. We have recently discovered that BMP1-3 isoform of the Bmp-1 gene circulates in the human plasma and is significantly increased in patients with acute bone fracture. We hypothesized that circulating BMP1-3 might have an important role in bone repair and serve as a novel bone biomarker. When administered systemically to rats with a long bone fracture and locally to rabbits with a critical size defect of the ulna, recombinant human BMP1-3 enhanced bone healing. In contrast, neutralization of the endogenous BMP1-3 by a specific polyclonal antibody delayed the bone union. Invitro BMP1-3 increased the expression of collagen type I and osteocalcin in MC3T3-E(1) osteoblast like cells, and enhanced the formation of mineralized bone nodules from bone marrow mesenchymal stem cells. We suggest that BMP1-3 is a novel systemic regulator of bone repair.

Surgical evaluation of magnetic resonance imaging findings in piriformis muscle syndrome

ObjectiveThe objective of this study was to evaluate the accuracy of magnetic resonance imaging (MRI) in the diagnosis of the piriformis muscle syndrome (PMS).Materials and MethodsIn ten patients, seven female and three male, with a long history of clinical symptoms of the PMS, an MRI was performed as the last preoperative diagnostic tool. All patients were imaged using 2T MR system (Elscint, Haifa, Israel). Axial and coronal spin-echo, fast spin-echo (FSE), and fat-suppressed FSE-weighted images were made through the pelvic region with 3-mm section thickness and a 0.5-mm gap to show the whole piriformis muscle and the course of sciatic nerve on its way out of the pelvis. A routine examination also included axial fast spin-echo T2, three-dimensional gradient echo.ResultsIn seven cases, an MRI abnormality for the PMS was found. In two women, the MRI demonstrated a bigastric appearance of the piriformis muscle with a tendinous portion between the muscle heads and the course of the common peroneal nerve through the muscle between the tendinous portions of the muscle. In one female patient, the common peroneal nerve passed through the hypertrophied piriformis muscle. In four patients, the MRI showed a hypertrophied aspect of the piriformis muscle and an anteriorly displaced sciatic nerve. All MRI findings were confirmed surgically. In three patients, no apparent abnormalities could be observed, but after a surgical treatment, i.e., a tenotomy of the piriformis muscle and neurolysis of the sciatic nerve, all symptoms disappeared.ConclusionIn piriformis muscle syndrome, MRI may demonstrate signal abnormalities of the sciatic nerve as well as its relationship with the normal and abnormal piriformis muscle.

Adverse effects of posterior lumbar interbody fusion using rhBMP-2.

To the Editor We read with great interest the recent article on the use of recombinant human bone morphogenetic protein 2 soaked into an absorbable collagen sponge (rhBMP-2/ ACS) in the posterior lumbar interbody fusion (PLIF) written by Meisel et al. [13]. However, a few corrections and clarifications are required to update this otherwise exceptionally significant article. Meisel et al. [13] mentioned a sheep distal femur model in which transient peri-implant osteolysis with regard to BMP overfilling and hyper-concentration has been observed [1], but several examples are present in the literature that clarify the pathophysiology and the relevance of the vertebral osteolysis much better. For instance, Seeherman and Wozney [15] have shown that a collagen sponge soaked with rhBMP-2 and placed in contact with trabecular bone of the distal femoral core defect in nonhuman primates resulted in significant transient bone resorption at 2 weeks after the surgery. This was not the case when they used a carrier with slower release of rhBMP (calcium phosphate matrix). The rapid release of rhBMPs at the bone surface which is in contact with the collagen sponge creates favorable conditions for significant osteoclastic reaction prior to the bone formation phase. According to a review of the interaction of BMPs with osteoclast lineage cells, BMPs in most of the reports had a stimulatory effect that up-regulated formation of osteoclasts, their bone resorptive capacity, or both of these phenomena [5]. As Meisel et al. [13] emphasized the note of Boden et al. [1] that parity between the distal femur and the central region of the vertebra may not be fully warranted as a clinically relevant spine model, we would like to emphasize a very significant article published by Laursen et al. [10] in this very Journal 10 years ago which definitively presents a relevant spinal model. It was the first report of trabecular bone resorptions after a clinical application of rhBMPs/ACS in proximity of vertebral bodies. The first report of trabecular bone resorptions after a clinical application of rhBMPs to our best knowledge was identified in a manuscript of Howell et al. [8]. The loss of bone volume in some of the cases after the rhBMP-2/ACS local alveolar ridge preservation or augmentation was noted between the 4and 8-week time points. Anyway, Laursen et al. [10] treated five patients with single-level unstable burst fracture and no neurological impairment with intracorporal rhBMP-7 transplantation, posterior fixation and posterolateral fusion. Radiographic and computed tomography (CT) evaluation after 3 and 6 months showed severe resorption of the whole anterior column at the site of transplantation, but after a year, new bone had started to fill in at the area of resorption. In all cases, there was a loss of correction with regard to anterior and middle column height and sagittal balance at the latest follow-up. Based on the obtained data, the authors by ethical obligation discontinued and redesigned the study. At this moment, we are interested in whether or not Meisel et al. [13] considered discontinuing and redesigning their study after they faced such vertebral resorptions in their patients at 3 months postoperatively (enrollment of the patients lasted from January until June of 2004). We had to emphasize that back in 2004 only a few researchers had some information about the resorptions and their clinical impacts, but that information for some reason has not been presented to T. Smoljanovic (&) I. Bojanic D. Delimar Department of Orthopaedic Surgery, Clinical Hospital Center Zagreb, School of Medicine, Zagreb University, Zagreb, Croatia e-mail: drsmoljanovic@yahoo.com

Relationship between 2000-m rowing ergometer performance times and World Rowing Championships rankings in elite-standard rowers

Abstract In this study, we evaluated the extent to which 2000-m rowing ergometer performance times predicted final rankings at the World Rowing Championships in a sample of 638 rowers of both sexes and body-mass classifications (i.e. open-category and lightweight rowers). Rowing ergometer performance times were examined using a questionnaire, and in 17 of 23 events they were positively correlated (P ≤ 0.049) with the final rankings at the Championships. The highest correlations were for the ergometer performance times achieved by rowers in lightweight mens single sculls (r = 0.78; P = 0.005), womens single sculls (r = 0.75; P = 0.002), mens single sculls (r = 0.72; P = 0.004), and lightweight mens double sculls (r = 0.72; P < 0.001). We used linear regression to establish regression equations to predict final rankings based on 2000-m rowing ergometer performance times for each event in which there was a correlation greater than r = 0.50. Although correlations in 12 events met this criterion, the large standard errors of the estimate hindered ranking predictions in all of the studied events. Regression equations could be used to determine the most probable 2000-m ergometer performance time for a rower to achieve specific rankings at the World Rowing Championships.

Osteochondritis dissecans of the elbow: excellent results in teenage athletes treated by arthroscopic debridement and microfracture.

Aim To extend the microfracture procedure, which has been proven successful on osteochondritis dissecans (OCD) lesions in the knee and ankle, to OCD lesions in the elbow. Methods Nine young patients were treated by arthroscopic debridement and microfracture by a single surgeon. The average age at operation was 15.0 years (median 15; range 12-19). The average length of the follow-up was 5.3 years (median 5; range 2-9). The follow-up included physical examination and patient interview with elbow function scoring. Success of treatment was determined according to pre-operative and follow-up Mayo Elbow Performance Index scores and the patients’ return to sports. Results Eight patients scored excellent results on the follow-up and 1 scored a good result. Four out of 9 patients were able to increase their training intensity, 2 returned to the same level of activity, 2 changed sports (due to reasons unrelated to the health of their elbow), and 1 left professional sports and started training only recreationally. No patients stopped participating in sports altogether. Conclusions We advocate arthroscopic microfracturing, followed by a strict rehabilitation regime, as a highly effective treatment for OCD of the humeral capitellum.

Surgical treatment of diaphyseal stress fractures of the fifth metatarsal in competitive athletes: long-term follow-up and computerized pedobarographic analysis.

BACKGROUND Proximal diaphyseal stress fractures of the fifth metatarsal are common in athletes. Conservative treatment has been shown to result in high rates of delayed union, nonunion, and refracture, so internal fixation has become the treatment of choice in competitive athletes. METHODS Twenty top-level athletes with diaphyseal stress fractures fixed with intramedullary malleolar screws were evaluated. Functional outcome was assessed by American Orthopaedic Foot and Ankle Society midfoot score. Static and dynamic maximum vertical force and peak plantar pressures were evaluated with a computerized pedobarograph. RESULTS Mean follow-up from surgery to interview was 10.3 years (range, 3.5-19.0 years). Clinical healing was 95%, and there has been one refracture (5%). The mean time from surgery to return to sport was 9 weeks (range, 5-14 weeks). Twelve athletes (60%) returned to a higher level of training, 7 (35%) to the same level, and 1 (5%) to a lower level compared with the level of training before injury. Average American Orthopaedic Foot and Ankle Society midfoot score was 93.8 (range, 85-100). During the computerized pedobarographic evaluations, 18 patients (90%) presented with varus of the metatarsus and the midfoot and 2 (10%) presented with a normal plantigrade foot. CONCLUSIONS Intramedullary malleolar screws can yield reliable and effective healing of fifth metatarsal stress fractures in athletes. Varus of the metatarsus and the midfoot were predisposing factors for stress fractures in this population of competitive athletes, and all were recommended to wear orthoses until their competitive careers were completed.

Osteochondritis dissecans of the first metatarsophalangeal joint: arthroscopy and microfracture technique.

Osteochondritis dissecans (OCD) is a localized disorder of the joint surface by which a segment of subchondral bone and its overlying cartilage become fragmented. Arthroscopic treatment of OCD of the first metatarsophalangeal joint consisted mainly of debridement and loose body removal. The microfracture technique for the treatment of OCD of the first metatarsophalangeal joint is presented for the first time. The technique has been shown to be a safe and technically uncomplicated first-line treatment.

Combined Anterior and Posterior Athroscopic Portals for Loose Body Removal and Synovectomy for Synovial Condromatosis

Background: Synovial chondromatosis is a rare disorder characterized by formation of cartilaginous bodies within the synovia of joints, tendon sheaths, and bursae secondary to a synovial metaplastic process. Recent literature has described using only an anterior approach to the ankle for these patients. It is unclear how well, if at all, synovectomy of the posterior part of the ankle joint was performed. Most recurrences occur years after surgery, as a result of incomplete synovectomy. Materials and Methods: We treated five patients (mean age 31.6 years; range, 21 to 63; four male, one female) with synovial chondromatosis of the ankle. We performed arthroscopic loose body removal and total synovectomy using both posterior and anterior ankle arthroscopic portals. At latest followup of a mean of 34.2 (range, 13 to 58) months, the functional result was assessed with the AOFAS score. Results: The AOFAS score improved from a mean of 67 (range, 58 to 77) points to a mean of 94 (range, 77 to 100) points. Overall patient satisfaction was good to excellent. We noted only one minor complication when a loose body was lost in the subcutaneous tissue, and was removed two weeks after the arthroscopy. Conclusion: Our experience in this small group of patients seems to indicate that a 2 portal approach with total synovectomy and removal of loose bodies gives the best result and minimizes the risk of recurrence. Level of Evidence: IV, Retrospective Case Series

Could chronic host inflammatory response be responsible for delayed onset of retrograde ejaculation after the labeled use of recombinant human bone morphogenetic protein-2?

Following the article by Muchow, Hsu, and Anderson (Spine J 2010 ; 10:e1-6), the authors of this Letter to Editor raise the question on whether the delayed onset of retrograde ejaculation after the labeled use of recombinant human bone morphogenetic protein-2 could be a result of chronic host inflammatory response.