Longstanding Sternoclavicular and Shoulder Pain: A SAPHO Syndrome Clinical Case Study

This SAPHO syndrome case study follows the assessment and investigation of a 49-year-old woman with a longstanding history of left-sided sternoclavicular joint, shoulder girdle, shoulder and cervical spine pain.

Her symptoms had persisted for around 20 years and she had seen a number of healthcare professionals without receiving a clear diagnosis.

A recent significant flare prompted further assessment. The clinical findings suggested that the sternoclavicular joint, rather than the glenohumeral shoulder joint itself, was central to the problem.

Specialist imaging and rheumatology assessment subsequently identified changes considered most consistent with SAPHO syndrome, a rare condition involving synovitis, acne, pustulosis, hyperostosis and osteitis.

Clinical case study: Patient information has been anonymised. This resource is provided for educational purposes and should not be used to diagnose or manage an individual medical condition.

Initial presentation

The patient presented with a recent flare of a longstanding history of left shoulder girdle, shoulder and cervical spine pain.

She described a constant dull throbbing around the left sternoclavicular joint.

The pain radiated:

• Along the clavicle

• Across the top of the shoulder

• Towards the deltoid region

• Up the left side of the cervical spine

• Towards the occipital region

She also experienced sharper catches of pain through the same distribution.

Pain intensity varied considerably, from approximately 2/10 to 10/10.

When symptoms became more severe, she reported that the whole left upper limb could ache.

She denied:

• Pins and needles

• Tingling

• Numbness

• Gait disturbance

• Loss of dexterity

• Symptoms associated with cervical arterial dysfunction

Aggravating factors and effect on daily life

The pain was aggravated by lying on the left side.

Movement of the left upper limb was also problematic, particularly when elevating the arm during activities such as:

• Washing her hair

• Dressing

• Loading through the left arm

• Weight-bearing through the upper limb

She managed the symptoms with paracetamol and changes to her activities.

One example was changing to an automatic car to avoid the repeated movement required to use a manual gear lever.

Her sleep was significantly disturbed by the pain.

A history stretching back around 20 years

The original symptoms had begun approximately 20 years earlier after a golf lesson.

The patient did not report a specific injury during the lesson.

However, the following day she woke with pain and swelling around the left sternoclavicular joint.

Soon afterwards she also developed:

• Left-sided cervical spine pain

• Left acromioclavicular joint pain

• Shoulder pain

At times, symptoms could involve the whole left upper limb.

Her GP initially advised use of a sling.

Since then, the patient had experienced varying levels of pain through the same general distribution.

Over the years she had consulted:

• Orthopaedic specialists

• Physiotherapists

• Osteopaths

• Chiropractors

Despite these appointments, she had never received a specific diagnosis.

She had last sought professional help approximately four to five years before the current assessment.

Recent flare of symptoms

Over the preceding six to seven weeks, the symptoms had gradually worsened.

The flare became severe enough that the pain was no longer manageable.

It was significantly affecting:

• Sleep

• Daily activities

• Quality of life

This prompted a fresh clinical assessment.

Physical examination

On examination in standing, the left shoulder girdle was elevated compared with the right.

There was visible overactivity and spasm affecting the upper fibres of the left trapezius.

The left scapula was held in a retracted position and remained close to the thoracic wall.

There was:

• A reduction in normal thoracic kyphosis

• Mild scoliosis through the cervical and thoracic spine

These changes were suspected to be maladaptive responses associated with the chronicity of the symptoms.

Cervical spine findings

Cervical spine range of movement was reasonably well preserved.

There was some myofascial restriction into:

• Right rotation

• Right side flexion

However, cervical spine movement did not reproduce or aggravate the symptoms.

Neurological testing of the upper limbs was unremarkable.

Shoulder girdle findings

Movement of the left shoulder girdle was markedly restricted.

There was very little depression from the elevated position and very little protraction or retraction, even with attempted facilitation.

Left shoulder movement was restricted to approximately:

• 90 degrees flexion

• 50 degrees abduction

External rotation remained full and caused only minimal pain.

Hand-behind-back movement was restricted to approximately the L5 level.

Importantly, the glenohumeral joint itself did not feel particularly restricted.

Instead, the major restriction appeared to involve movement of the scapula and clavicle.

Rotator cuff testing was unremarkable.

Sternoclavicular joint findings

There was very marked tenderness over the left sternoclavicular joint and around the articulation between the first rib and the manubrium.

The area felt:

• Thickened

• Chronically swollen

• Very tender

There was also tenderness along the medial clavicle, although this reduced further laterally.

The acromioclavicular joint was tender to palpation.

The upper trapezius and scalene muscles were tender, shortened and in spasm.

The first and second ribs appeared elevated on the left.

Initial clinical reasoning

The patient was advised to contact her GP to review analgesia and try to bring the pain back under better control.

Given the very long duration of symptoms, there was consideration of a component of central sensitisation.

However, this was not thought to account fully for the presentation.

The provisional diagnosis was chronic sternoclavicular joint dysfunction of uncertain origin.

The apparent restriction in shoulder movement was suspected to be secondary to substantial dysfunction involving:

• The scapulothoracic joint

• The acromioclavicular joint

• The sternoclavicular joint

The sternoclavicular joint was considered the likely origin of the problem.

There was a suspicion that previous assessments and imaging may have focused predominantly on the glenohumeral joint and may not have included the full clavicle, sternoclavicular joint and acromioclavicular joint.

It was also suspected that there might be no major structural abnormality within the glenohumeral joint itself, which could help explain why a clear diagnosis had not previously been established.

Differential diagnoses considered

Several possible explanations for the sternoclavicular joint dysfunction were considered, including:

• Displacement of the sternoclavicular joint articular disc, potentially affecting clavicular rotation

• Rapid-onset osteoarthritis with periodic flares

• Involvement of subclavius affecting the ability of the clavicle to depress

• A previous episode of costochondritis affecting the first rib and subsequently the sternoclavicular joint

• An undiagnosed Friedrich's condition

There was also suspicion of a mild neurogenic thoracic outlet component, which could potentially have explained the intermittent diffuse symptoms affecting the left upper limb.

Given the complexity and duration of the presentation, an orthopaedic opinion was considered appropriate.

The patient elected to seek this privately.

A clinical summary was sent to the consultant, specifically highlighting concerns relating to the sternoclavicular joint.

Orthopaedic assessment and further imaging

The patient was seen by a shoulder consultant and was subsequently referred to a rheumatologist.

Investigations included:

• Left shoulder X-ray

• Chest X-ray

• Left shoulder MRI

• Sternoclavicular joint MRI

• CT imaging

The shoulder X-ray, chest X-ray and general shoulder MRI were effectively normal apart from mild chronic supraspinatus tendinosis.

This supported the earlier suspicion that the glenohumeral joint itself was not the main source of the problem.

Left shoulder MRI findings

The MRI reported:

• Normal acromioclavicular joint appearance

• Normal coracoacromial arch morphology

• A small amount of fluid in the subacromial bursa, without features of bursitis

• Mild tendinosis involving the anterior supraspinatus tendon

• No partial thickness tear

• Normal appearances of infraspinatus, teres minor and subscapularis

• Intact glenoid labrum and chondrolabral junction

• Normal glenohumeral articular cartilage

• Unremarkable glenoid version and morphology

• Normal long head of biceps tendon

• Intact biceps anchor

• Normal rotator cuff muscle volume and signal for age

The overall conclusion was mild chronic supraspinatus tendinosis, with an otherwise normal MRI examination of the left shoulder.

Sternoclavicular imaging findings

The sternoclavicular imaging produced much more significant findings.

There was a large volume of dystrophic ossification involving the left costoclavicular ligament.

This extended along the lower border of the medial end of the left clavicle and involved the inferior capsular margin of the sternoclavicular joint.

The heterotopic bone showed evidence of oedema, suggesting a reactive component.

There was also:

• Oedema within the adjacent medial clavicle

• Arthrosis of the inferomedial left sternoclavicular joint

• Osteophyte formation at the medial end of the clavicle

• Small areas of subarticular bone change on the manubrial side

• Arthrosis affecting the right sternoclavicular joint

• Probable subarticular erosions and small cystic changes on the manubrial side

The articular disc of the left sternoclavicular joint remained intact.

There was no significant joint effusion or active synovitis.

The superior sternoclavicular and interclavicular ligaments were intact.

Sternoclavicular joint alignment remained normal on both sides.

There was no periarticular soft-tissue swelling or fluid collection.

Imaging conclusion

The radiology conclusion described:

• Chronic inflammatory changes

• Secondary degenerative arthropathy of both sternoclavicular joints

• More significant involvement on the left

• Probable chronic erosions on the manubrial side

• Large-volume heterotopic bone formation through the left costoclavicular ligament

• Periosteal bone formation along the inferior clavicular cortex

The manubrial arthropathy was not associated with sclerosis.

The imaging initially raised the possibility of a seronegative inflammatory arthropathy or SAPHO syndrome.

Further CT imaging was recommended to characterise the erosive changes and heterotopic bone formation.

Rheumatology assessment

The patient was subsequently reviewed by a Consultant Rheumatologist.

The working diagnosis was:

Possible SAPHO syndrome: synovitis, acne, pustulosis and hyperostosis.

At the same time, she was being investigated for knee pain and had a history of previous sacral fractures and anxiety.

Her medication included:

• Paracetamol or ibuprofen as required

• Sertraline

An ultrasound of the right hand and further blood tests were arranged.

Additional clinical history considered by rheumatology

The rheumatology assessment recorded the longstanding shoulder history and the fact that the patient had seen numerous specialists over more than two decades.

Imaging showed features of chronic inflammation and secondary degenerative arthropathy affecting both sternoclavicular joints, particularly on the left.

The CT demonstrated:

• Bilateral erosive sternoclavicular joint arthropathy

• Periarticular bone production

• Extra-articular heterotopic ossification

• Osteitis affecting the manubrium

• Osteitis affecting the medial end of the left clavicle

The findings were considered most consistent with SAPHO syndrome.

The osteitis phase of the condition appeared quiescent on the more recent MRI.

A previous pelvic MRI had also shown possible left-sided chronic sacroiliitis with iliac sclerosis and small erosions.

The patient had previously fractured her sacrum on two occasions.

She had also recently developed left knee pain and had been assessed for a possible meniscal tear.

In addition, she had developed some stiffness in her fingers.

Paracetamol and ibuprofen provided some symptom relief.

There was no reported family history of:

• Psoriasis

• Inflammatory bowel disease

Her father had undergone bilateral total hip replacement and her grandmother had undergone bilateral knee replacement.

Rheumatology examination

The patient mobilised normally.

There was:

• Marked pain around the left sternoclavicular region during left shoulder movement

• Palpable deformity of the left sternoclavicular area compared with the right

• Left knee joint-line tenderness

• A positive extensor lag at the knee

• Tenderness affecting the right middle proximal interphalangeal joint

These findings were considered unusual and potentially consistent with SAPHO syndrome.

Further rheumatology findings

Further review of the CT concluded that there were chronic inflammatory changes with secondary degenerative arthropathy affecting both sternoclavicular joints, particularly the left.

There was extensive heterotopic bone formation along the left costoclavicular ligament and periosteal bone formation along the lower surface of the clavicle.

Following discussion with a Consultant Radiologist, the imaging was considered more consistent with SAPHO syndrome than a seronegative arthropathy.

Notably, the patient had never experienced acne or pustulosis.

Ultrasound of the right hand did not identify inflammatory arthropathy.

It did show:

• Mild thickening of the radial side of the D3 A1 pulley

• Mild arthrosis affecting the D3 distal and proximal interphalangeal joints

Previous pelvic imaging was also reviewed.

Although there were features of mild left sacroiliitis with sclerosis and small erosions, these were considered more likely to reflect degenerative change.

At this stage, the disease process appeared to be predominantly isolated to the sternoclavicular joint rather than clearly affecting multiple joints.

Treatment considerations

Given the severity of the structural changes, the patient was advised to discuss whether a surgical option might be appropriate.

Disease-modifying immunosuppressant medication was another potential consideration, although there was uncertainty about how much difference this would make given the existing structural changes.

She was also advised not to remain in one position for prolonged periods while working at a desk.

Regular breaks and stretching were recommended.

A follow-up rheumatology review was planned.

Surgical management

The patient subsequently underwent surgery.

The heterotopic ossification around the left sternoclavicular joint was surgically excised.

The right sternoclavicular joint was injected.

The diagnosis recorded following this stage of management was SAPHO.

Understanding the sternoclavicular joint

The sternoclavicular joint is an important component of the shoulder girdle because it connects the upper limb to the axial skeleton.

Like other joints, it can be affected by:

• Trauma

• Infection

• Inflammatory pathology

• Degenerative pathology

However, these conditions are relatively uncommon at the sternoclavicular joint compared with many other joints.

The literature referenced in the original case study notes that this can contribute to delayed diagnosis and inappropriate intervention.

The sternoclavicular joint is a diarthrodial saddle joint formed by:

• The sternal end of the clavicle

• The clavicular notch of the manubrium

• The cartilage of the first rib

Stability is provided by:

• The intra-articular disc

• The anterior sternoclavicular ligament

• The posterior sternoclavicular ligament

• The costoclavicular ligament

• The interclavicular ligament

The joint allows substantial movement.

The source literature describes approximately:

• 30 degrees anteroposterior glide

• 30 degrees superoinferior pivot

• 45 degrees axial rotation

The original case study also references a management algorithm from Edwin et al. for non-traumatic sternoclavicular joint swelling, considering infective, osteoarthritic, inflammatory and rarer causes.

What is SAPHO syndrome?

SAPHO is a condition of unclear cause with a variable presentation that can be difficult to diagnose.

The name represents five features:

• Synovitis

• Acne

• Pustulosis

• Hyperostosis

• Osteitis

The syndrome was first classified in 1987.

It is characterised by periods of exacerbation and remission, with severity varying

considerably between patients.

It is considered rare, although the literature suggests its true prevalence may be underestimated.

SAPHO does not always involve skin symptoms

An important aspect of this case was that the patient had never experienced acne or pustulosis.

The literature referenced in the case study states that skin and osteoarticular symptoms do not necessarily need to occur together.

Approximately 15% of adults with SAPHO may never develop skin involvement.

This can make recognition and diagnosis more difficult.

Increased awareness is therefore important because delayed diagnosis can allow progression of osteoarticular disease.

Typical pattern of SAPHO

Symptoms can initially be unilateral, although many patients eventually develop bilateral involvement.

The literature cited in the case study describes the condition as being seen predominantly in:

• Young to middle-aged adults

• Women

• Children

The onset is usually gradual, although trauma may sometimes precede symptoms.

Pain can be severe and disabling.

Other findings may include:

• Soft-tissue swelling

• Heat

• Redness

• Reduced active movement

• Morning stiffness

Areas commonly affected

The axial skeleton is described as being involved in around 91% of cases and peripheral joints in around 36%.

Approximately 65% to 90% of patients are reported to have involvement of the anterior chest wall.

This can include:

• Sternoclavicular joint

• Manubriosternal joint

• Costochondral region

• Costosternal region

The anterior chest wall is the most commonly affected area.

Other sites can include:

• Thoracic spine

• Lumbar spine

• Cervical spine

Progression of bony changes

The literature referenced in this case describes three stages of lesion development.

Stage 1

Disease is localised around the costoclavicular ligament and may initially appear as an enthesopathy.

Stage 2

Arthropathy develops at the sternoclavicular joint.

Changes can include:

• Osteolysis

• Osteosclerosis

These changes may affect:

• Medial clavicle

• Sternum

• First rib

• Costal cartilage

Stage 3

There is progression of:

• Osteosclerosis

• Hyperostosis

• Hypertrophy

Ossification of the costoclavicular ligament and first costal cartilage can occur.

Bony masses may develop between the clavicle and first rib and ankylosis of the sternoclavicular joint has been described in adults.

This pattern was considered consistent with the changes identified in this patient.

Imaging and diagnosis

In adults, X-rays may eventually show characteristic findings such as:

• Expanded bone

• Sclerosis

• Osteolysis

• Periosteal reaction

• Enthesopathic new bone formation

However, these appearances can sometimes be difficult to distinguish from infection or neoplasia.

This is one reason why specialist investigation and appropriate referral can be important.

Management of SAPHO

According to the literature reviewed in the original case study, treatment is directed towards:

• Symptom relief

• Modification of the disease process

Care may involve rheumatology and, where appropriate, dermatology.

There is some evidence supporting targeted corticosteroid injection.

Surgical resection may be considered where there is:

• Severe deformity

• Painful loss of function

However, recurrence following surgery can occur.

Blood markers such as ESR and CRP may be moderately raised.

HLA-B27 positivity has also been reported in a proportion of patients.

What causes SAPHO?

The exact cause of SAPHO remains poorly understood.

The literature discussed in the case study considers possible links with:

• Persistent infection involving low-virulence organisms

• Autoimmune processes triggered by infection

• Genetic factors

An increased frequency of HLA-B27 positivity has been reported, although the relationship is much weaker than in conditions such as ankylosing spondylitis.

SAPHO appears to share some characteristics with:

• Spondyloarthropathies

• Autoimmune disease

• Autoinflammatory disorders

Recognition is important because an incorrect diagnosis may result in unnecessary invasive procedures or prolonged antibiotic treatment.

Limitations of the evidence

SAPHO is rare.

As a result, the case study notes that there do not appear to be randomised controlled trials evaluating treatment and management options.

Much of the available evidence comes from:

• Individual case studies

• Small case series

The literature cited suggests that non-steroidal anti-inflammatory drugs and disease-modifying antirheumatic drugs may provide benefit when used appropriately.

Steph's reflections on the case

At the time of this case, SAPHO was a condition Steph had not previously encountered.

The patient's Consultant Rheumatologist reportedly advised that she was the first SAPHO patient he had seen in five years, reinforcing how rarely the condition may present in practice.

Reflecting on the management, the decision to refer the patient promptly for specialist assessment and investigation was considered appropriate.

One feature that was perhaps not recognised strongly enough at the initial assessment was the inflammatory component of the presentation, particularly the repeated flare-ups in symptoms.

However, identifying this earlier would not have changed the decision to refer onwards.

The significance of repeated consultations

Another important learning point from this case was the long history of repeated consultations.

The patient had seen many different professionals over approximately 20 years without receiving a clear explanation for her symptoms.

This became an important clinical consideration in itself.

Despite the longstanding pain, she appeared to be a resilient, active individual without many of the psychosocial features often associated with chronic pain presentations.

The symptoms themselves remained:

• Specific

• Persistent

• Debilitating

This reinforced the importance of reconsidering the diagnosis rather than assuming the presentation was simply a longstanding chronic pain condition.

Impact on the patient

Over a relatively short period following the more recent assessment, the patient underwent more medical investigations and specialist consultations than she had experienced over much of the previous 20 years.

She also underwent uncommon and painful surgery to remove the heterotopic bone.

The aim was to reduce symptoms and potentially improve function of the left upper limb.

The patient's existing anxiety was also an important consideration during this period of increased medical investigation and treatment.

Learning from the case

Following review of the literature, particularly the work by Edwin et al., the case increased Steph's awareness of potential sternoclavicular joint pathology.

For future patients presenting with focal sternoclavicular pain and swelling, the case reinforced consideration of:

• Plain X-ray imaging

• Inflammatory blood screening

• Appropriate specialist referral

The management flow chart published by Edwin et al. was also considered potentially useful as a clinical pathway for non-traumatic sternoclavicular presentations in primary care.

There was consideration of whether such a pathway should be formalised within the department, although the rarity of these conditions in community MSK clinics raised questions about how frequently it would be required.

Ultimately, the case reinforced the importance of remaining alert to conditions that may not previously have been encountered in clinical practice.

Key learning points

This SAPHO syndrome case study highlights several important aspects of advanced musculoskeletal assessment:

1. Longstanding pain should still be reassessed carefully when the clinical picture does not fit a common musculoskeletal condition.

2. The sternoclavicular joint can be an important source of shoulder girdle symptoms.

3. Normal shoulder imaging does not necessarily exclude pathology elsewhere within the shoulder girdle.

4. Repeated unresolved presentations over many years can be an important clinical clue.

5. Rare inflammatory conditions can present without all of their traditionally associated features.

6. Appropriate specialist referral and further investigation are important when findings are unusual.

7. Reflection on rare cases can improve future clinical assessment and decision-making.

About Dunham Physio

Dunham Physio is based in Dunham Massey, near Altrincham.

Steph is an Advanced Musculoskeletal Practitioner and First Contact Practitioner with extensive experience assessing common and complex musculoskeletal presentations.

A thorough MSK assessment considers not just where pain is felt, but the behaviour of symptoms, movement patterns, clinical examination findings and whether further investigation or onward referral may be required.

If you are experiencing persistent shoulder, neck, joint or musculoskeletal pain and would like an assessment, contact Dunham Physio to arrange an appointment.

References

Duan N, Chen X, Liu Y, Wang J and Wang Z (2016). Multimodal imaging findings of SAPHO syndrome with no skin lesions: A report of three cases and review of the literature. Experimental and Therapeutic Medicine; 12; 2665–2670.

Edwin J, Ahmed S, Verma S, Tytherleigh-Strong G, Karuppaiah K and Sinha J (2018). Swelling of the sternoclavicular joint: review of traumatic and non-traumatic pathologies. EFORT Open Reviews; 3; 471–484.

Henriques C, Sousa M, Panarra A and Riso N (2011). The dark side of SAPHO syndrome. BMJ Case Reports; 10.1136/bcr.11.2011.5197.

Nguyen M, Borchers A, Selmi C, Naguma S, Cheema G and Gershwin M (2012). The SAPHO Syndrome. Seminars in Arthritis and Rheumatism; 42; 254–265.