Spectrum of musculo-skeletal disorders in sickle cell disease in Lagos, Nigeria

Journal of Orthopaedic Surgery and Research Spectrum of musculo-skeletal disorders in sickle cell disease in Lagos, Nigeria Rufai A Balogun 0 Dike C Obalum 0 Suleiman O Giwa 0 Thomas O Adekoya-Cole 0 Chidiebere N Ogo 0 George O Enweluzo 0 0 Department of Surgery, College of Medicine, University of Lagos (CMUL)/ Lagos University Teaching Hospital (LUTH) , PMB 12003, Lagos , Nigeria Background: Sickle cell anemia (SCA) is a common genetic disease in Nigeria. Past studies from West Africa focused on isolated aspects of its medical and surgical presentations. To the best of our knowledge, the musculoskeletal presentations amongst Nigerians with SCA have not been documented in a single all encompassing study. This work aims to prospectively document the musculo-skeletal disease burden among SCA patients. Methods: In a prospective study of 318 consecutive patients with genotype-confirmed SCA at the Lagos University Teaching Hospital (LUTH), the musculo-skeletal pathologies, anatomic sites, grade of disease, age at presentation and management outcome were recorded over a one-year period. Data obtained were analyzed using Epi-Info software version 6.0. Data are presented as frequencies (%) and mean values (SD) as appropriate. Results: The HbSS genotype occurred in 296 (93.0%), while 22 (7.0%) were HbSC. 100 (31.4%) patients with average presenting haemoglobin concentration of 8.2 g/100 ml in the study group, presented with 131 musculoskeletal pathologies in 118 anatomic sites. Osteomyelitis 31 (31%) and septic arthritis 19 (19%) were most commonly observed in children less than 10 years. Skin ulcers and avascular necrosis (AVN) occurred predominantly in the older age groups, with frequencies of 13 (13.0%) and 26 (26.0%) respectively. 20 (71.5%) of diagnosed cases of AVN presented with radiological grade 4 disease. The lower limbs were involved in 84 (71.1%) of sites affected. Lesions involving the spine were rare 11 (0.9%). Multiple presentations occurred in 89 (28.0%) of patients; 62 (69.7%) of which were children below 10 years. Conclusions: Musculo-skeletal complications are common features of sickle cell anaemia seen in 31.4%. Infectious aetiologies predominate with long bones and joints of lower limbs more commonly affected by osteomyelitis and septic arthritis. Healthcare providers managing SCA should be aware of the potential morbidity and mortality of these conditions to ensure early diagnosis and adequate management. - Background Sickle cell disease (SCD) is a group of inherited haemoglobinopathies occurring mainly in Negroid populations in and out of Africa, characterized by a predominance of haemoglobin S (HbS) in the erythrocytes [1]. It was first recognized by James B. Herrick [2] in 1910 when he described abnormal sickle-shaped cells in an anaemic patient of Negroid extraction. Pauling et al [3] discovered the presence of abnormal haemoglobin in patients with sickle cell disease in 1949. SCD is the most frequent haemoglobinopathy in the world [4,5] and currently the second most common genetic disease after Downs syndrome [5]. Sickle cell disease is said to affect between 2-3% of the Nigerian population [1]. Sickle cell anaemia (SCA) occurs when there is homozygote HbSS or composite heterozygote HbSC [1]. It is primarily a disease of haemopoetic system in which the skeleton bears the brunt of its complications [6]. Bone changes in SCA occur due to marrow hyperplasia, tissue ischaemia and infarction due to vaso-occlusion [7-9]. Musculo-skeletal manifestations constitute up to 80% of indications for presentation in hospital in SCA during their life time [10-14]. Pain is the principal complaint either acute following skeletal or soft tissue infarction or chronic secondary to avascular necrosis of bone at various joints [15]. Most studies of musculo-skeletal presentations of SCA in Nigeria have focused on selected disease conditions [8,10,16-19]. SCA causes a heavy burden on the society by the high morbidity and premature death associated with it [20]. This study was designed to prospectively document, using a comprehensive approach, the spectrum and frequency of musculo-skeletal presentations among patients with SCA. This would provide useful data on the burden of musculo-skeletal disease in SCA, for further research, infrastructural and manpower planning towards appropriate care delivery. Methods This prospective study was conducted over a 12-month period between June 2000 and May 2001 at Lagos University Teaching Hospital (LUTH), Lagos, Nigeria. LUTH is one of the foremost tertiary hospitals in Nigeria. The study protocol was approved by the Health Research and Ethics Committee of the hospital. Informed consent was obtained from all study participants or their proxies. Cases included were consecutively presenting patients with Hb genotype SS or SC attending one of 4 sites in the hospital: orthopaedic outpatient clinic, accident and emergency department, haemotology clinic (adult SCD clinic) and paediatric outpatient department. Through a pre-arranged notification network, the investigators were informed of any case of SCA presenting during the study period, and each patient was then evaluated by one of the investigators using the standardized format developed for the study. Musculo-skeletal complaints were defined as any problem affecting bones or/and its associated soft tissues. Patients with SCA with congenital musculo-skeletal anomalies were excluded. Clinical evaluation and relevant investigations were carried out as part of standard management of these patients to arrive at a diagnosis by the authors. The diagnosis of AVN was made using plain x-rays as the institution at the time of study had no facilities for CT, MRI or Isotope scan. This was stated as the main reason for the absence of stage 1 disease in our study. All patients with a diagnosis of septic arthritis had emergency arthrotomy and drainage. Aspirates were sent for culture and antibiotic sensitivity. Active ulcers were considered as ulcers but those with unspecific scars on the ankles were not considered as such. Osteomyelitis was diagnosed based on clinical evaluation, needle puncture and intra operative aspirate of purulent fluid with positive cultures. A standard proforma was filled following detailed history and physical examination with requisite investigations to confirm the diagnosis. Variables recorded included age, sex, weight, height, genotype, anatomic site(s) involved, clinical features and the diagnosis. Data obtained were analyzed using Epi-Info software version 6.0. Data are presented as frequencies (%) and mean values (SD) as appropriate, and compared using either the chi square test (for proportions) or students T test for mean values. P < 0.05 is taken as statistically significant. Results Demography Three hundred and eighteen patients with SCA were studied. 100 (31.4%) patients with average presenting haemoglobin concentration of 8.2 g/100 ml had 131 musculo-sk (...truncated)