Year 2 LOC2: Locomotor 2

Catherine is a 45-year-old woman who is referred by her GP to the rheumatology clinic because of widespread joint pain and difficulty in walking.  She has, over the last 2-years, lost weight (going from 160kg to 74kg).  Catherine reports that the joint pain began in her ankles and has spread to her knees, hips and shoulders.  She reports that the weight loss is in part due to the use of high daily doses of an antacid which she is using for its laxative properties. 

On examination, there are no joint deformities.  There is no reduction in the range of movement but the movement of the joints is painful.  The neurological examination was normal.  Proximal muscle weakness was noted in both lower limbs.  A blood sample is taken.

Serum calcium                                             2mmol/L (2.2-2.6mmol/L)

Serum phosphate                                        0.68mmol/L (0.8-1.4mmol/L)

Serum alkaline phosphatase                    173 U/L (45-105 U/L)

Serum 25-hydroxy-vitamin D3                   36 pg/mL (20-76 pg/mL)

Serum 1,25 dihydroxy-vitamin D3             110 ng/mL (10-35 ng/mL)

Intact PTH                                                     19 U/L (11-54 U/L)

Her renal function was also checked and a urine analysis undertaken.

24 hour calcium                                           1391 mg/24hr (42-353 mg/24hr)

24 hour phosphorus                                               0.56 mg/24hr (400-1300 mg/24hr)

X-rays of the knees and hips so no loss of joint space and no loss of joint line characteristics.  What are seen are stress fractures both in the femoral neck and the upper part of the tibias.  Looser lines were also evident in the pelvis. A transiliac bone biopsy after double tetracycline labelling was obtained from the right iliac crest.  The biopsy showed normal bone volume but osteoid volume was markedly elevated and well as osteoid thickness.  No tetracycline uptake was evident and the bone surface was positive for aluminium using the aurin tricarboxylic acid method. 

Catherine was started on 50,000 units of vitamin D every other day, calcium carbonate 600mg four time daily and neutral potassium phosphate 250mg four times daily and was told about the dangers of the long term antacid used and she agreed to stop taking it.  At the follow up a month later the serum calcium and phosphate were within the normal range and Catherine reported that she felt stronger and the pain had lessened.

Helen is 46 years old, she has bilateral hip osteoarthritis. Helen's health problems started at the age of 11, her parents had taken her to her GP after a fall on a cross-country run as she was complaining of increasing levels of pain in her hips.  After numerous investigations, she had been eventually diagnosed with bilateral Perthes disease.  Once the Perthes had run its course unfortunately, there was damage to both femoral heads.  Over the years, Helen has tried the full range of pain medications of over 15 different analgesics and anti-inflammatory drugs, covering the full range of the analgesic ladder. Her current medication, oxycodone, this has so far been the best choice, optimizing pain relief whilst minimizing side effects. Helen continues to be under the care of the orthopedic surgeons, who are contemplating a revision for her failed left total hip replacement which she had 5 years ago. Helen remains independent and self-caring despite deterioration in her levels of pain and physical functioning.

Helen had trained as a radiographer, but following the failure of a hip replacement she became a wheelchair user, this was not felt to be compatible with her job and so she had to give it up. The loss of her job has had significant impact on Helen's mood with the loss of her independence, freedom of movement, and loss of ability to take an active part in her interests and hobbies plus the associated financial insecurity.  She wants to remain independent.

Karl is a 9 year old boy who is brought into the Emergency department by his parents.  He is unable to weight bear due to a painful swelling of his left foot he is also generally unwell.  Both Karl and his parents confirm no preceding trauma. 

On taking a history Karl states that 10 days previously he had woken up normally but had been unable to walk on his left foot.  After 2 days of pain in his left foot had not improved so his parents had taken him to the GP, who had suggested that he have an X-ray to rule out any trauma.  At this time Karl felt well in himself and the x-rays showed no abnormalities a diagnosis of Sever’s disease was given and he was discharged to have physiotherapy in the community.

However, Karl’s foot became increasingly painful and so his parents brought him back into the Emergency department.  The left foot was now erythematous, hot, swollen around the ankle and heel.  He was constitutionally unwell, pyrexial and dehydrated and complains of severe pain in his left foot.  There is lymphangitis that extends up the left leg and soft tissue swelling around the ankle joint.  A blood sample is taken and the results come back with the following:

ESR                                        68mm/hr (0-25 mm/hr)

C-reactive protein                198mg/L (0-18mg/L)

White Blood cell count        11.1x10⁹/L (4.5 – 14.5 x10⁹/L)

Neutrophils                           8.0x10⁹/L (1.8 – 8 x10⁹/L)

The plain radiographs now showed increased density within the calcaneal apophysis.  He also sent for an emergency MRI scan which revealed osteomyelitis of the calcaneal bone with the infection spreading to surrounding soft tissue.

Karl was taken immediately to theatre for drainage of the left foot abscess and drilling of the os calcis for osteomyelitis.  A sample of the pus was sent for culturing, sensitivity, gram-staining and acid fast culture.  A complete washout of the wound was undertaken with 6 litres of saline and the further washout of the drilled os calcis was performed.  Aqueous iodine and ribbon gauze was used to pack the cavity and hold open the incision.  No antibiotics were administered until the results of the pus sample were obtained, then flucloxacillin and co-amoxiclav were administered intra-venously coupled with fusidic acid.  Two further washout were performed on the final washout granulation tissue was observed and the wound was closed.  The IV antibiotics were continued for two weeks, then he was discharged home and continued with a 4 week flucloxacillin and fusidic acid administered orally.

At 6 weeks he was reviewed and was able to fully weight bear and at further follow up appointment at 3 months showed no complications, and Karl was playing football again.

Ben is a 32 year old fireman; he attends your GP clinic because of stiffness and pain in his lower back which has been affecting him for a couple of months, he thinks he has just strained his back at work. Because he has not attended your clinic for over a year you decide to do a full examination at the same time.  On examination he is fit and healthy with no remarkable findings except for stiffness in the cervical and lumbar regions of the vertebral column, as gauged in the GALS examination.  On the arms GALS examination of his hands you note that he has pitting and discoloration with ‘oil-drop’ appearance and onycholysis of the nails of most fingers.  There is also some swelling of the distal interphalangeal joints of both hands.  There are no other deformities of note in the upper limb.  On inspection of his feet the same nail problems are noted.  When you ask him about the nail problems he says he thought it was just a fungal nail infection like those advertised in the Sunday supplements and on the tube, he has thought about treating them but it never seemed to bad enough for him to do anything about it, and anyway his job means he never has nice nails anyway.  His father had similar problems with his nails and also tended to have dry scaly patches on his knees and elbows.

You take a blood sample and send it away, a week later the result come back negative for rheumatoid factor although the ESR and C-reactive protein levels are raised.  You prescribe Diclofenac 100mg and ask him to come back in a month and that you may prescribe methotrexate if the problem does not improve.  He is confused and wonders what his nails have to do with his back problem.