Enfeksiyon kemiğe ulaşmamış.

Because kemiğe is the dative form of kemik (bone).

Here, ulaşmak means to reach, and it normally takes a noun in the dative case, so:

• kemik = bone
• kemiğe = to the bone

There is also a sound change:

• final k often becomes ğ before a vowel-initial suffix
• so kemik + e becomes kemiğe

So the phrase kemiğe ulaşmak means to reach the bone.

Ulaşmamış comes from the verb ulaşmak (to reach).

It breaks down like this:

• ulaş- = reach
• -ma- = negative
• -mış = inferential/reported past

So literally it means something like:

• has apparently not reached
• it turns out it has not reached
• in natural English here: hasn't reached

In this sentence, the third-person singular ending is zero, so ulaşmamış by itself already means he/she/it has apparently not reached.

This is a very common question, because both can refer to the past, but they do not feel exactly the same.

• ulaşmadı = did not reach
  This is the direct/simple past. It sounds more like a straightforward fact stated directly.

• ulaşmamış = apparently/it turns out it has not reached
  This is the inferential/reported past. It often suggests the speaker knows this from evidence, a report, a test result, or later discovery.

In a medical context, ulaşmamış sounds very natural, because the speaker may be reporting a finding such as from an examination or scan.

No. It can mean several related things:

• reported information: someone told you
• inference: you conclude it from evidence
• new realization/discovery: you have just found out

In a sentence like Enfeksiyon kemiğe ulaşmamış, it often sounds like a conclusion based on medical evidence, not necessarily gossip or hearsay.

So it is better to think of -mış as indirectly known rather than only someone said so.

Because enfeksiyon is the subject of the sentence, and subjects are normally in the nominative, which has no special ending in Turkish.

So:

• enfeksiyon = infection
• no extra ending is needed because it is the thing doing the reaching

If you changed it to enfeksiyonu, that would be a different grammatical role, usually a definite direct object, which would not fit this sentence.

Turkish does not have articles like English the and a/an.

That means Turkish often leaves article meaning to the context.

So:

• enfeksiyon can mean infection, an infection, or the infection
• kemiğe can mean to a bone or to the bone

In this medical sentence, context makes the infection and the bone the most natural English translation.

Yes, when ulaşmak means to reach, it normally takes the dative.

Examples:

• eve ulaştı = he/she arrived at home
• hedefine ulaştı = he/she reached his/her goal
• bana ulaştı = it reached me / it got to me
• kemiğe ulaştı = it reached the bone

So kemiğe is exactly what you would expect after ulaşmak.

Yes. This is a very normal Turkish word order:

• Enfeksiyon = subject
• kemiğe = complement with dative
• ulaşmamış = verb

Turkish often places the verb at the end, so this sentence has a neutral, natural order.

You can move words around for emphasis, but Enfeksiyon kemiğe ulaşmamış is the standard unmarked version.

The ğ in Turkish is usually not pronounced like a hard English g.

In kemiğe, it mainly softens or lengthens the sound between vowels. Depending on the speaker, it may sound roughly like:

• ke-MEE-e
• or something close to ke-MI-ye

The important point is:

• do not pronounce it like English g in go

So ğ here is soft and smooth, not a strong consonant.

Yes, that is grammatical, but the nuance changes.

• Enfeksiyon kemiğe ulaşmadı = The infection didn’t reach the bone.
• Enfeksiyon kemiğe ulaşmamış = The infection hasn’t/apparently hasn’t reached the bone.

The -mış version is especially natural when the speaker is giving a result or conclusion, such as after examining the patient or seeing test results.

So both are possible, but ulaşmamış has a slightly more indirect or evidential flavor.